RU2439101C2 - Rubber composition and pneumatic tyre cover using rubber composition - Google Patents

Abstract

FIELD: machine-building industry.

SUBSTANCE: rubber composition is made by mixing low-molecular polymer (B) based on conjugated dienes characterised by the presence of functional group, content of aromatic vinyl composition in the interval from 0 to less than 5% (wt), and weight-average molecular weight measured without chain breaking as a result of modification by gel permeation chromatography method and calculated to polystyrene, no less than 2000, but less than 150000, and filling element (C) to high-molecular rubber component (A), which is specific by weight-average molecular weight measured without chain breaking as a result of modification by gel permeation chromatography method and calculated to polystyrene, no less than 2000, but less than 150000 and their vulcanisation. The functional group of B polymer is selected from tin-, silicon- and nitrogen containing groups. The nitrogen containing group is derived from a group consisting of isocyanine, tio isocyanine, aminobenzophenone compositions, carbamide derivatives, ketimine or aldimine compositions containing relation C=N-C and cyclic amide compositions.

EFFECT: invention allows for producing good balance between flibility at low temperature and low resistance to rolling.

38 cl, 14 tbl, 16 ex

Description

Technical field

The present invention relates to a rubber composition and a pneumatic tire using a rubber composition, and more specifically, to a rubber composition characterized by an exceptionally good balance between low rolling resistance and flexibility at low temperature.

State of the art

Recently, there has been an urgent need for low fuel consumption and vehicle safety, combined with the need to tackle carbon dioxide emissions worldwide due to growing environmental concerns. To meet such a need, it is necessary to reduce rolling resistance and improve grip characteristics of a tire with a wet road surface, such as wet grip characteristics of a tire, dry grip characteristics of a tire and the like, which is related to tire performance. As a way to reduce tire rolling resistance, it is effective to use a rubber composition characterized by a reduced loss tangent (tan δ) and low heating during deformation as a rubber composition deposited on the tread portion of a tire. It is known that butadiene rubber, traditionally and widely used in the tread portion of a tire, or styrene-butadiene copolymer rubber, which is characterized by a low level of styrene and a low level of vinyl, is characterized by excellent flexibility at a low temperature, since they have low in comparison with other synthetic rubbers glass transition temperature (Tg).

However, since the loss tangent (tan δ) of such a rubber composition is small, when using butadiene rubber or styrene-butadiene copolymer rubber having a low styrene content and a low vinyl content in the tread, there is a problem of obtaining sufficient adhesion characteristics of the tire with road surface.

As methods for producing a rubber composition characterized by low heating during deformation, reducing the amount of filler such as carbon black, silicon dioxide and the like, using carbon black having a large particle size, and the like are considered. However, in any cases, for the rubber composition, it is impossible to avoid a deterioration in the reinforcing effect, wear resistance and adhesion characteristics of the tire with the road surface on a wet road surface. As part of another method for producing a rubber composition characterized by low heating during deformation, a number of techniques have been developed to improve the dispersibility of the filler in the rubber composition. Among them, the most effective is the method in which the conjugated diene-based polymer obtained from anionic polymerization using alkyl lithium is modified by a functional group interacting with a filler (for example, see documents JP-B-H05-87530, JP-A-H06-49279 and JP-A-S62-207342). However, when a modified conjugated diene-based polymer is used as a rubber component with a large amount of plasticizer, especially aromatic oil, being mixed, the effect of improving the dispersibility of the filler is not disclosed sufficiently, and the problem arises for the rubber composition that it is impossible sufficiently improve processability, low heating during deformation, fracture characteristics and wear resistance. A technique is also known for imparting excellent flexibility at low temperature while maintaining manufacturability, but the effect is insufficient and rolling resistance cannot be improved at the same time (for example, see JP-A-H10-53671).

On the other hand, in order to ensure the adhesion characteristics of the tire with the road surface, as the rubber composition deposited on the tread portion of the tire, it is preferable to use a rubber composition characterized by a high storage modulus of the complex elastic modulus (G '), so it is necessary to develop a rubber composition characterized by a low loss tangent (tan δ) and a high storage modulus of the complex elastic modulus (G '). In this regard, as a method for improving the storage modulus of a complex elastic modulus (G ') in a rubber composition, a method is known in which the amount of carbon black mixed with the rubber composition is increased. However, although in the case of an increase in the amount of carbon black mixed with the rubber composition, the accumulation modulus of the complex elastic modulus (G ') of the rubber composition can be improved, but at the same time the loss tangent (tan δ) of the rubber composition also increases, which for rubber Composition worsens low heating during deformation, and, in addition, the rubber composition increases the Mooney viscosity, which leads to the problem of deterioration of manufacturability. Despite the existence of a method of adding a plasticizer to improve manufacturability, wear resistance and rolling resistance deteriorate, as mentioned earlier. Therefore, the need to develop a rubber composition characterized by a balance between the aforementioned conflicting performance characteristics is becoming ever more urgent.

Specifically, in general, a rubber composition applied to the tread portion of a studless tire is required to provide flexibility at a low temperature (the term “low temperature” as used herein refers to the temperature while traveling on ice and snow and corresponds to a temperature in the range from about -20 to 0 ° C), so often it is a rubber composition that brings the modulus of elasticity at a low temperature to a low level as a result of using a polymer having viscous glass transition temperature, such as butadiene rubber (BR), natural rubber (NR) and the like. However, a rubber composition containing an admixed polymer having a low glass transition temperature, such as butadiene rubber (BK), natural rubber (NK), and the like, is characterized by a low value, as mentioned previously, so that it will be difficult to give the tire sufficient adhesion characteristics of the tire to road surface. In general, when elastic modulus decreases at low temperature, there is a tendency to decrease elastic modulus at high temperature (the term “high temperature” used in this document refers to the temperature affecting control during normal movement), so for commonly used studless tires there is the problem of the impossibility of maintaining sufficient characteristics of the adhesion of the tire with the road surface in the high temperature region. In addition, during normal movement on a wet road surface, a sufficient coefficient of friction is not obtained, and thus, in the case of a studless tire using the aforementioned rubber composition, it is difficult to improve the adhesion properties of the tire on a wet road during normal movement surface (wet grip performance).

On the other hand, various techniques have been previously developed to improve the friction force for the tread rubber itself. As such a technique, for example, a method is known in which a rubber composition is used as a tread rubber, obtained by mixing a foaming agent into the rubber component, and then cavities are formed in the matrix formed from the rubber component as a result of foaming, . For example, JP-A-H09-194640, as a technique for improving wet grip performance and ice grip and grip performance (ice grip performance on ice) describes a method for blending a foam component into a rubber component and a liquid polymer characterized by a weight average molecular weight of several tens of thousands. However, the surface of the rubber of the tread obtained by this method covers a large number of pores, so that on the icy and snowy road surface, a dehydration effect and an edge effect that increase the friction force can develop, while there is a problem of deterioration of the tire fracture resistance due to coating the surface with a large number of pores .

Disclosure of invention

The inventors observed and found that when using the liquid polymer described in JP-A-H09-194640, wet grip performance improves, but when using the liquid polymer having a relatively high glass transition temperature, flexibility at a low temperature deteriorates, so that the glass transition temperature of the used liquid polymer should be limited to relatively low values. Therefore, there are still opportunities for the tire to improve the adhesion characteristics of the tire to the road surface on ice, even in the case of using the technique described in JP-A-H09-194640.

Therefore, the objectives of the invention are to solve the aforementioned problems of commonly used techniques and offer a rubber composition characterized by an exceptionally good balance between flexibility at low temperature and low rolling resistance. In addition, it is another object of the invention to provide a rubber composition capable of imparting excellent tire adhesion characteristics to the tire on ice and wet adhesion properties of the tire as a result of its use, at least in the area of contact with the ground of the tread portion tires. In addition, it is another object of the invention to provide a rubber composition capable of imparting resistance to fracture while maintaining the storage modulus of the complex elastic modulus (G ') at high temperature, as well as improving the adhesion of the tire to the road surface on ice and snow (adhesion characteristics) tires with road pavement on ice) as a result of its use, at least in the area of contact with the soil of the tread portion of the tire. Moreover, an additional object of the invention is to provide a pneumatic tire using such a rubber composition.

The inventors conducted a variety of studies aimed at achieving the above objectives, and found that the flexibility of the rubber composition at low temperature and low rolling resistance can be extremely well balanced as a result of using a low molecular weight polymer based on a conjugated diene characterized by the presence of at least one functional group and srednevekovoi molecular weight in the specified range, and mixing it with high mol a molecular rubber component characterized by the indicated weight average molecular weight, and as a result, the invention was made.

In addition, the inventors conducted additional studies and found that when a low molecular weight polymer based on a conjugated diene characterized by at least one functional group and the indicated weight average molecular weight was mixed with the rubber component, and the expanding cavities of the resulting As a result of the rubber composition, it is possible to significantly reduce the storage modulus of the complex elastic modulus (G ') at low temperature without significant reducing the storage modulus of the complex elastic modulus (G ') at high temperature, whereby the adhesion characteristics of the tire to the road surface on ice can be improved, and in addition, the adhesion characteristics of the tire to the wet road surface can be maintained since the tan δ value at low temperature does not significantly deteriorate, and as a result, the invention was made. In addition, the inventors found that in the case of choosing a weight average molecular weight of a low molecular weight polymer based on a conjugated diene in the specified range and limiting it to this range, (1) the adhesion of the tire to the road surface on ice can be significantly improved, or (2) the resulting as a result of the rubber composition, the fracture resistance will increase and the storage modulus of the complex elastic modulus (G ') will be improved at high temperature, but the complex storage modulus may also decrease th elastic modulus (G ') at low temperature.

That is, the first rubber composition according to the invention is characterized by admixing a low molecular weight polymer (B) based on a conjugated diene having at least one functional group, with an aromatic vinyl compound content of less than 5% (wt.) And a weight average molecular weight mass measured without breaking the chain as a result of modification by gel permeation chromatography and recalculated to polystyrene, not less than 2000, but less than 150,000, and filler (G ') to high molecular weight rubber component (A), characterized by a weight average molecular weight, measured without chain termination as a result of modification by gel permeation chromatography and converted to polystyrene of not less than 150,000.

In addition, the second rubber composition according to the invention is a rubber composition obtained by admixing a low molecular weight polymer (B) based on a conjugated diene having at least one functional group with an aromatic vinyl compound content of less than 5% ( wt.), and weight average molecular weight, measured without breaking the chain as a result of modification by gel permeation chromatography and converted to polystyrene, not less than 2000 and 150,000, to the rubber compo ententa (A), formed from at least one material selected from natural rubber and diene-based synthetic rubbers, characterized by a weight average molecular weight, measured without breaking the chain as a result of modification by gel permeation chromatography and converted to polystyrene, not less than than 150,000, characterized by the inclusion of cavities in the rubber matrix of the rubber composition.

In addition, the third rubber composition according to the invention is characterized in that the low molecular weight polymer (B) based on the conjugated diene in the second rubber composition is characterized by a weight average molecular weight measured without chain termination as a result of modification by gel permeation chromatography and converted to polystyrene in the range from 2000 to 50,000. In addition, the fourth rubber composition according to the invention is characterized in that the low molecular weight polymer (B) is based e conjugated diene in the second rubber composition is characterized by a weight average molecular weight, measured without an open circuit as a result of modification by gel permeation chromatography and calculated for polystyrene, ranging from 50,000 to 150,000.

In addition, the term “measured without chain termination as a result of modification” means the production of a polymer by suppressing the activity of an active terminal group using a chain termination agent such as alcohol and the like, without carrying out a modification reaction as a result of the addition of a modifying agent or of a combination of high molecular weight forms that cause a jump in molecular weight, and the like, at the end of the polymerization reaction, and after that, the polymer is measured. This is true if a functional group containing nitrogen and the like is included in the initiator.

In a preferred embodiment of the third rubber composition according to the invention, the extractability in chloroform for the case of extraction in chloroform for 48 hours upon completion of vulcanization is not less than 60% (wt.) Based on the weight of the low molecular weight polymer (B) based on conjugated diene .

In a preferred embodiment of the fourth rubber composition according to the invention, the extractability in chloroform for the case of extraction in chloroform for 48 hours upon completion of vulcanization is not less than 60% (wt.) Based on the weight of the low molecular weight polymer (B) based on conjugated diene .

Any one of the rubber compositions of the invention, selected in the range of the first to fourth, preferably contains from 1 to 60 parts by weight of a low molecular weight polymer (B) based on a conjugated diene, based on 100 parts by weight of the rubber component (A).

In a preferred embodiment of any one of the rubber compositions of the invention, selected in the range of the first to fourth, the low molecular weight polymer (B) based on the conjugated diene in the part formed by the conjugated diene compound is characterized by a vinyl content in the range of 5 to 80% ( wt.).

In another preferred embodiment, any one of the rubber compositions of the invention, selected in the range of the first to fourth, low molecular weight polymer (B) based on a conjugated diene is a butadiene homopolymer or a styrene-butadiene copolymer.

In another preferred embodiment, any one of the rubber compositions of the invention selected in the range of the first to fourth functional group in the low molecular weight polymer (B) based on a conjugated diene is at least one selected from the group consisting of tin-containing a functional group, a silicon-containing functional group, and a nitrogen-containing functional group. At present, the conjugated diene-based low molecular weight polymer (B) is preferably that obtained by modifying the active polymerization center using a tin-containing compound, a silicon-containing compound, or a nitrogen-containing compound. In addition, the tin-containing compound or the silicon-containing compound is more preferably a chain termination modifying agent, described by the following formula (I):

,

,

where R ¹ independently selected from the group consisting of an alkyl group containing carbon atoms in an amount of from 1 to 20, a cycloalkyl group containing carbon atoms in an amount of from 3 to 20, an aryl group containing carbon atoms in an amount of from 6 to 20, and an aralkyl group containing carbon atoms in an amount of from 7 to 20; Z represents tin or silicon; X independently represents chlorine or bromine; a is 0-3, and b is 1-4, provided that a + b = 4.

If in any one of the rubber compositions of the invention selected in the range from the first to the fourth, the functional group in the low molecular weight polymer (B) based on the conjugated diene will be at least one selected from the group consisting of a tin-containing functional group of a silicon-containing functional group and a nitrogen-containing functional group, then the nitrogen-containing functional group is preferably selected from the group consisting of a substituted amino group described with eduyuschey formula (II):

,

,

where R ² independently represents an alkyl group containing carbon atoms in an amount of from 1 to 12, a cycloalkyl group or an aralkyl group;

and a cyclic amino group described by the following formula (III):

,

,

where R ³ represents an alkylene group comprising 3-16 methylene groups, a substituted alkylene group, an oxyalkylene group or an N-alkylaminoalkylene group. In addition, the silicon-containing functional group is preferably a functional group formed from hydrocarbyloxysilane.

Compounds that are characterized by structural formulas (I) to (III) and which can be used as modifying agents of the invention are disclosed, for example, in documents US 2009/0239974, US 5393721, JP-H5-320421, US 5587420, JP-H7 -82422, EP 0661298, JP-H11-189616.

In the first rubber composition according to the invention, the low molecular weight polymer (B) based on a conjugated diene is preferably characterized by a weight average molecular weight measured without chain termination as a result of gel permeation chromatography modification and converted to polystyrene of not less than 20,000 but less than 150,000 more preferably in the range of 50,000 to 120,000.

In the third rubber composition according to the invention, the low molecular weight polymer (B) based on a conjugated diene is preferably characterized by a weight average molecular weight measured without breaking the chain as a result of gel permeation chromatography modification and converted to polystyrene ranging from 2000 to 30000.

In the fourth rubber composition according to the invention, the low molecular weight polymer (B) based on a conjugated diene is preferably characterized by a weight average molecular weight measured without chain termination as a result of gel permeation chromatography modification and converted to polystyrene ranging from 50,000 to 120,000.

In another preferred embodiment, any one of the rubber compositions of the invention, selected in the range of the first to fourth, further comprises a filler (C) in an amount in the range of 20 to 100 parts by weight per 100 parts by weight of the rubber component (A). At the moment, any one of the rubber compositions of the invention, selected in the range from the first to the fourth, preferably contains from 30 to 90 parts by weight of filler (C) based on 100 parts by weight of the rubber composition (A). In addition, filler (C) is preferably carbon black and / or silicon dioxide.

In another preferred embodiment, any one of the rubber compositions of the invention, selected in the range of the first to fourth, contains silicon dioxide in an amount not less than 10 parts by mass based on 100 parts by mass of the rubber component (A).

In another preferred embodiment of the first rubber composition according to the invention, the rubber component (A) contains at least one material selected from the group consisting of a copolymer (D) of an aromatic vinyl compound - a conjugated diene compound, a polymer (E) conjugated diene compound and natural rubber. Currently, a styrene-butadiene copolymer is preferred as a copolymer of an aromatic vinyl compound - conjugated diene compound (D), and a butadiene homopolymer is preferred as a polymer (E) of a conjugated diene compound. In addition, the copolymer (D) of the aromatic vinyl compound-conjugated diene compound and the polymer (E) of the conjugated diene compound preferably include at least one functional group. In addition, the functional group in the copolymer (D) of the aromatic vinyl compound - conjugated diene compound and the polymer (E) of the conjugated diene compound is more preferably at least one selected from the group consisting of a tin-containing functional group, a silicon-containing functional group, and nitrogen-containing functional group.

In yet another preferred embodiment of any one of the rubber compositions of the invention, selected in the range of the first to fourth, the total amount of low molecular weight polymer (B) based on a conjugated diene and plasticizer (F) is in the range of 5 to 80 parts by weight per 100 mass parts of the rubber component (A). At the moment, the total amount of admixed low molecular weight polymer (B) based on a conjugated diene and plasticizer (F) is preferably in the range of 5 to 60 parts by mass per 100 parts by mass of the rubber component (A). In addition, the proportion of the low molecular weight polymer (B) based on the conjugated diene in the total amount of the low molecular weight polymer (B) based on the conjugated diene and plasticizer (F) is preferably not less than 20% (wt.).

In any one of the rubber compositions of the invention, selected in the range of the second to fourth, the proportion of cavities in the rubber composition is preferably in the range of 5 to 35%.

In yet another preferred embodiment of any one of the rubber compositions of the invention, selected in the range of the second to fourth, the foam component (G) is further contained in the rubber component (A). At the moment, any one of the rubber compositions according to the invention, selected in the range from the second to the fourth, is preferably obtained by mixing from 1 to 20 mass parts of the foaming agent (G) based on 100 mass parts of the rubber component (A), and then vulcanization and foaming. In addition, the foaming agent (G) is preferably at least one selected from the group consisting of azodicarbonamide, dinitrosopentamethylene tetraamine, azobisisobutilonitrile, toluenesulfonyl hydrazide and a toluenesulfonyl hydrazide derivative.

The rubber composition of the invention is preferably a rubber composition for manufacturing a tire.

The first pneumatic tire according to the invention is characterized by the use of the aforementioned rubber composition for manufacturing a tire in a tire member. As the tire element, it is preferable to mention the tread part, the side part, the part formed by the filler cord of the rim, the part formed by the rubberized layer of the tire carcass, and the reinforcing rubber part for the tire with deflated pressure.

The second pneumatic tire according to the invention is characterized by the use of the aforementioned rubber composition for the manufacture of the tire, at least in the area of contact with the ground of the tread portion. At the moment, the second pneumatic tire is preferably a studless tire, more preferably a studless tire for a passenger car.

The invention provides a rubber composition characterized by an exceptionally good balance between flexibility at a low temperature and low rolling resistance as a result of mixing a low molecular weight polymer based on a conjugated diene, characterized by the presence of at least one functional group and the indicated weight average molecular weight and level of content aromatic vinyl compound to the high molecular weight rubber component characterized by weight average molecular weight.

In addition, a rubber composition obtained by admixing a low molecular weight polymer based on a conjugated diene characterized by the presence of at least one functional group and the indicated weight average molecular weight and level of aromatic vinyl compound content to the rubber component characterized by the specified weight average molecular weight can be provided. mass and including cavities in the rubber matrix, and capable of improving the adhesion characteristics of the tire with the road covered on ice and snow (grip characteristics of the tire with the road surface on ice) without deterioration of the grip characteristics of the tire with the road surface on a wet road surface (grip characteristics of the tire with a wet road surface) during normal movement. In addition, (1) a rubber composition capable of imparting excellent tire adhesion characteristics to the tire on ice and wet grip characteristics of the tire, or (2) a rubber composition capable of imparting fracture resistance while maintaining an integrated storage modulus may be provided. modulus of elasticity (G ') at high temperature, as well as improving tire adhesion characteristics of the tire with the road surface on ice and snow (adhesion characteristics in Ryshkov land portion on ice) by limiting the weight average molecular weight of the low molecular weight polymer based on a conjugated diene additionally specified range.

In addition, a pneumatic tire using the aforementioned rubber composition may be provided.

The best way to implement the invention

The invention will now be described in detail. The first rubber composition according to the invention is characterized by admixing a low molecular weight polymer (B) based on a conjugated diene characterized by the presence of at least one functional group, an aromatic vinyl compound content of less than 5% (wt.), And a weight average molecular weight measured without chain termination as a result of modification by gel permeation chromatography and recalculated to polystyrene not less than 2000 and less than 150,000, and filler (C) to high molecular weight in rubber component (A), characterized by a weight average molecular weight, measured without an open circuit as a result of modification by gel permeation chromatography and calculated for polystyrene of not less than 150,000.

The second rubber composition according to the invention is a rubber composition obtained by admixing a low molecular weight polymer (B) based on a conjugated diene characterized by the presence of at least one functional group and an aromatic vinyl compound content of less than 5% (wt. ), and the weight average molecular weight, measured without chain termination as a result of modification by gel permeation chromatography and recalculated to polystyrene, not less than 2000 and 150,000, to beech component (A), formed from at least one material selected from natural rubber and diene-based synthetic rubbers, characterized by a weight average molecular weight measured without breaking the chain as a result of modification by gel permeation chromatography and converted to polystyrene, not less than than 150,000, characterized by the inclusion of cavities in the rubber matrix of the rubber composition.

The second rubber composition according to the invention includes cavities in its rubber matrix, so that due to the dehydration effect and the edge effect on the icy and snowy road surface, the adhesion characteristics of the tire to the ice on the ice and the adhesion characteristics of the tire to the wet road are high. In addition, the second rubber composition according to the invention contains a low molecular weight polymer based on a conjugated diene characterized by the presence of an introduced functional group and the indicated weight average molecular weight, so that it has a high affinity for a filler such as silicon dioxide and the like, and dispersibility filler improves. For this reason, the second rubber composition according to the invention has improved physical properties, such as fracture characteristics, a decrease in G ′, and the like.

The third rubber composition according to the invention is a rubber composition obtained by admixing a low molecular weight polymer (B) based on a conjugated diene characterized by the presence of at least one functional group and an aromatic vinyl compound content of less than 5% (wt. ), and the weight average molecular weight, measured without chain termination as a result of modification by gel permeation chromatography and converted to polystyrene, in the range from 2000 to 50,000, to the rubber component (A), formed from at least one material selected from natural rubber and diene-based synthetic rubbers, characterized by a weight average molecular weight measured without chain termination as a result of modification by gel permeation chromatography and recalculated polystyrene, not less than 150,000, characterized by the inclusion of cavities in the rubber matrix of the rubber composition.

The third rubber composition according to the invention includes cavities in its rubber matrix, so that due to the dehydration effect and the edge effect on the icy and snowy road surface, the adhesion characteristics of the tire with ice on the ice and the adhesion characteristics of the tire with wet road surface will be high. In addition, in the third rubber composition according to the invention, a low molecular weight polymer (B) based on a conjugated diene is used, characterized by the presence of at least one functional group and a level of aromatic vinyl compound content of less than 5% (wt.) and the weight average molecular weight measured without breaking the chain as a result of gel permeation chromatography modification and converted to polystyrene in the range from 2000 to 50,000, which improves the dispersion filler ’s adjustability, which improves the fracture characteristics, and in addition, the adhesion characteristics of a tire to a road surface on ice and snow can be significantly improved (characteristics of a tire to road adhesion on ice), since the storage modulus of the complex elastic modulus (G ') at - 20 ° C decreases. Moreover, based on the results of measuring the temperature dispersion of the storage modulus of the complex elastic modulus (G '), it is possible to confirm the achievement of a significant level by the decrease in the storage modulus of the complex elastic modulus (G') in the low-temperature region, which affects the adhesion characteristics of the tire with a wet road surface or traction characteristics of the tire with the road surface on ice in comparison with the temperature region in the vicinity of 50 ° C, which affects the control during normal movement with the exception of movement on ice and snow. In addition, the rubber composition obtained by admixing a low molecular weight polymer (B) based on a conjugated diene to said rubber component (A) shows high adhesion properties of the tire to the wet road surface due to the inherent effect of the liquid polymer. Therefore, by using the rubber composition according to the invention, at least in the area of contact with the ground, the tread portion of the pneumatic tire can significantly improve both the adhesion characteristics of the tire to the road surface on ice and the adhesion characteristics of the tire to wet road surface.

The fourth rubber composition according to the invention is a rubber composition obtained by admixing a low molecular weight polymer (B) based on a conjugated diene characterized by the presence of at least one functional group and a level of aromatic vinyl compound content of less than 5% (wt. ), and the weight average molecular weight, measured without breaking the chain as a result of modification by gel permeation chromatography and recalculated to polystyrene, not less than 50,000, but higher than 150,000 to the rubber component (A), formed from at least one material selected from natural rubber and diene-based synthetic rubbers, characterized by a weight average molecular weight measured without chain termination as a result of modification by gel permeation chromatography and recalculated to polystyrene, not less than 150,000, characterized by the inclusion of cavities in the rubber matrix of the rubber composition.

The fourth rubber composition according to the invention includes cavities in its rubber matrix, so that due to the dehydration effect and the edge effect on the icy and snowy road surface, the adhesion characteristics of the tire on the ice and the adhesion characteristics of the tire on a wet road surface will be high. In addition, in the fourth rubber composition according to the invention, instead of a plasticizer such as aromatic oil and the like, a low molecular weight polymer (B) based on a conjugated diene is used, characterized by a weight average molecular weight measured without breaking the chain as a result of gel permeation modification chromatography and converted to polystyrene, not less than 50,000, but less than 150,000, so that due to the presence of a low molecular weight polymer (B) based on a conjugated diene about definiteness molecular weight different from the molecular weight of conventional plasticizers can be improved accumulation unit complex elastic modulus (G ') at high temperature and resistance to fracture. On the other hand, since the low molecular weight polymer (B) based on a conjugated diene contains carbon-carbon double bonds in its molecule, it has a high affinity for a filler such as carbon black and the like, and the dispersibility of the filler is improved. For this reason, the fourth rubber composition according to the invention can suppress the increase in the storage modulus of the complex elastic modulus (G ') at a low temperature, which ensures good adhesion of the tire to the road surface on ice. Moreover, since the rubber composition is characterized by a low tan δ value at high temperature, in the case of using the rubber composition, at least in the area of contact with the ground of the tread portion of the tire, the tire will have low rolling resistance and excellent fuel consumption.

The rubber component (A) used in the rubber compositions of the invention, selected in the range from the first to the fourth, is a high molecular weight rubber component that requires a weight average molecular weight, measured without chain termination as a result of modification by gel permeation chromatography and converted to polystyrene not less than 150,000, preferably in the range from 200,000 to 2,000,000. In the case of a weight-average molecular weight of the rubber component (A) within the aforementioned range, when a low molecular weight polymer (B) based on a conjugated diene is mixed with it, a decrease in Mooney viscosity and a deterioration in fracture and wear resistance can be suppressed, which will provide excellent processability. In addition, the rubber component (A) preferably contains at least one material selected from the group consisting of a copolymer (D) of an aromatic vinyl compound, a conjugated diene compound, a polymer (E) of a conjugated diene compound, and natural rubber.

There are no particular restrictions on the rubber component (A) used in the first rubber composition of the invention, and can be selected from the group of high molecular weight rubber components including natural rubber and copolymer (D) of an aromatic vinyl compound, a conjugated diene compound, and a polymer (E) of a conjugated diene compound, which are diene-based synthetic rubbers. As the rubber component (A), any of the unmodified and modified rubbers can be used. There are no particular restrictions on natural rubber and isoprene rubber (IR), and all commercially available natural rubbers and isoprene rubbers can be used. In addition, the copolymer (D) of the aromatic vinyl compound - conjugated diene compound is particularly preferably a styrene-butadiene copolymer. At the moment, mention may be made, for example, of 1,3-butadiene, 1,3-pentadiene, isoprene, 1,3-hexadiene and the like as a conjugated diene compound. Among them, 1,3-butadiene is particularly preferred. On the other hand, as an aromatic vinyl compound used in copolymerization with a conjugated diene compound, mention should be made, for example, of styrene, α-methylstyrene, 1-vinylnaphthalene, 3-vinyltoluene, ethylvinylbenzene, divinylbenzene, 4-cyclohexylstyrene, 2,2,6 Tolylstyrene and the like. Of these, styrene is preferred. The polymer (E) of the conjugated diene compound includes a homopolymer of a conjugated diene compound, a copolymer of conjugated diene compounds and the like, and preferably it is polybutadiene as a homopolymer of a conjugated diene compound. Natural rubber, component (D) and component (E) can be used individually or in combination of two or more components.

In the first composition of the invention, a conjugated diene-based polymer used in the rubber component (A) (including a copolymer (D) of an aromatic vinyl compound — a conjugated diene compound and a polymer (E) of a conjugated diene compound) can be prepared by various methods such as emulsion polymerization, solution polymerization, and the like. As the polymerization system, any system selected from a batch polymerization system and a continuous polymerization system can be used. A preferred preparation method includes the following. That is, it is obtained by polymerizing a monomer (s) including a conjugated diene compound in an inert solvent, preferably a hydrocarbon solvent, in the presence of an initiator such as an organometallic compound and the like, preferably an organolithium compound or lithium amide compound. No particular restrictions are imposed on the hydrocarbon solvent, and it includes, for example, n-pentane, n-hexane, n-heptane, cyclohexane, benzene, toluene and the like. Among them, cyclohexane and n-hexane are preferred. These hydrocarbon solvents can be used individually or in combination of two or more components. The organolithium compound used as the initiator is preferably a lithium hydrocarbon compound or a lithium amide compound which contain at least one bonded lithium atom and carbon atoms in an amount of from 2 to 20. For example, n-butyllithium, sec. β-butyl lithium, ethyl lithium, n-propyl lithium, t-octyl lithium, phenyl lithium and the like, and N-butyl lithium is preferred. These initiators based on organolithium compounds can be used individually or in combination of two or more components.

In addition, the conjugated diene polymer as components (D) and (E) used in the first rubber composition according to the invention preferably includes at least one functional group, and more preferably it is a modified polymer including a tin-containing functional group or a silicon-containing functional group, or a modified polymer comprising a nitrogen-containing functional group or in the end position. It is preferable that these modified polymers suppress a decrease in the elastic modulus due to an increase in temperature, but they can also suppress heating during deformation in a rubber composition containing mixed carbon black, in the case of introducing a tin atom or nitrogen atom, or in a rubber composition containing a mixed reinforcing inorganic filler such as silicon dioxide and the like, in the case of the introduction of a silicon atom. Moreover, in component (D) or (E), the level of polymer containing at least one functional group selected in its molecule or end position selected from a tin-containing functional group, a nitrogen-containing functional group and a silicon-containing functional group is preferably not less than 50% (wt.), more preferably not less than 80% (wt.).

In addition, it is particularly preferred that components (D) and (E) have a branched structure. A branched structure can be introduced as a result of using an initiator characterized by a functionality of at least three, a modifying agent characterized by a functionality of at least three, a monomer comprising an active group during polymerization in an amount of not less than two, and the like. . It is preferable to use a modifier characterized by functionality equal to at least three. The above modified polymer is prepared by a well known method. Usually it is obtained by starting the polymerization using an organolithium initiator and then adding various modifiers to the polymer solution, including the lithium active end group (see documents JP-B-H06-89183, JP-A-H11-29659 and the like). The modifier is preferably loaded at the end of the polymerization. The coupling reaction agent is a halide such as tin halide, silicon halide and the like. Halogen in the coupling reaction agent is generally fluoro, chloro, bromo or iodo. Among them, chlorine is preferred. In addition, tin or silicon atoms are preferred elements of group VIa, and tin is particularly preferred. For example, a tin atom can be introduced using a tin compound such as tin tetrachloride, tributyltin, dioctyltin dichloride, dibutyltin dichloride, triphenyltin chloride and the like.

A nitrogen atom can be introduced using an isocyanate compound such as 2,4-tolylene diisocyanate, diisocyanate diphenylmethane, MDI (4,4'-methylenediphenyldiisocyanate) (including a commercially available product, commonly known as the crude MDI, which is a mixture analogues containing a different number of cores) and the like; thioisocyanate compounds; an aminobenzophenone compound such as 4,4'-bis (diethylamino) benzophenone, 4- (dimethylamino) benzophenone and the like; a urea derivative such as 1,3-dimethyl-2-imidazolidinone, 1,3-diethyl-2-imidazolidinone, 1,3-dimethyl-3,4,5,6-tetrahydropyrimidine and the like; or another nitrogen-containing compound, for example a ketimine or aldimine compound containing a C = N — C bond, such as 4-dimethylaminobenzylideneaniline and the like, a cyclic amide compound such as N-methylpyrrolidone and the like. Furthermore, it can be introduced by reaction with a polymerizable vinyl compound or a conjugated diene compound including a nitrogen-containing group such as 2-vinylpyridine, 4- (N, N-dimethylamino) methyl styrene and the like. In addition, if a lithium amide compound is used as a polymerization initiator, a (co) polymer can be obtained comprising a nitrogen-containing functional group in the end group initiating the polymerization and an active polymerization center in the other end position, so that as a result of the reaction between (co) the polymer and the modifying agent of the reaction of chain termination and without modification can be obtained rubber component (A), including one functional group. As the lithium amide compound, lithium hexamethyleneimide, lithium pyrrolidide, lithium piperidide, lithium heptamethyleneimide, lithium dimethyl amide, lithium diethylamide, lithium diphenyl diamide, lithium diamide diamide diamide diamide lithium, lithium N-methylpiperazide, lithium ethylpropylamide, lithium ethylbutylamide, lithium methylbutylamide, lithium ethylbenzylamide, lithium methylphenethylamide, N-lithiomorpholine, N-methylhomopiperazine, N-ethylhomopiperazine, N-butyl ilgomopiperazin and the like. Among them, cyclic lithium amide compounds such as lithium hexamethyleneimide, lithium pyrrolidide, lithium piperidide, lithium heptamethyleneimide, lithium dodecamethyleneimide and the like are particularly preferred, and lithium hexamethyleneimide and lithium pyrrolidide are particularly preferred. In a preferred embodiment, the lithium amide compound is prepared previously in the presence of a solubilized component (SOL), as described in the patent (SOL patent is cited), or in the absence of a solubilized component, as described in the patent (patent citing limiting the structure of the amine without using SOL), and then it can be used as a polymerization initiator. Moreover, the lithium amide compound can be obtained in the polymerization system (in situ (locally)) without prior refinement for use as a polymerization initiator, as described in the patent (InSitu patent is cited).

The silicon atom can be introduced by any well-known methods in which an alkoxysilyl group or a silanol group can be introduced, but there is a preferred method in which said hydrocarbyloxysilane compound (which includes a C1-C20 alkoxysilyl group and / or an allyloxy silyl group, and optionally a C1-C20 hydrocarbidene group, additionally linked in the same molecule to a functional group such as an epoxy group, an amino group, a ketimino group, an amido group, a carboxylic acid ester group, a carbonic ester group, an isocyanate group, a thioisocyanate group, a nitrile group and the like) that are reacted with a polymerization-active end group. The hydrocarbyloxy silane compound includes a compound obtained by incomplete condensation of the hydrocarbyloxy groups. The hydrocarbyl oxysilane compound, specifically, includes, for example, a compound obtained by linking two to four C1-C20 hydrocarbyl groups to a silicon atom, such as tetraethoxysilane, methyltriphenoxysilane and the like, by way of example, not including another functional group other than a hydrocarbon group. As an alkoxysilane compound including an epoxy group, specifically, mention should be made of 2-glycidoxyethyltrimethoxysilane, 2-glycidoxyethyltriethoxysilane, (2-glycidoxyethyl) methyldimethoxysilane-3-methoxydioxypropylmethoxyphenylmethoxyphenylmethoxyphenylphenolphenol (2-glycidoxypropyl) methyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl (methyl) diethoxysilane, 2- (3,4 uh hydroxy cyclohex) ethyl (methyl) dimethoxysilane and the like.

As an alkoxysilane compound including an amino group, mention should be made of a hydrocarbyloxysilane compound including a disubstituted amino group, such as 3- (N, N-dimethylamino) propyl (triethoxy) silane, 3- (N, N-dimethylamino) propyl (trimethoxy) silane, 3 - (N, N-diethylamino) propyl (triethoxy) silane, 3- (N, N-diethylamino) propyl (trimethoxy) silane, 2- (N, N-dimethylamino) ethyl (triethoxy) silane, 2- (N, N dimethylamino) ethyl (trimethoxy) silane, 3- (N, N-dimethylamino) propyl (diethoxy) methylsilane, 3- (N, N-dibutylamino) propyl (triethoxy) silane and the like; and a hydrocarbyloxy silane compound comprising a cyclic amino group such as 3- (1-hexamethyleneimino) propyl (triethoxy) silane, 3- (1-hexamethyleneimino) propyl (trimethoxy) silane, 3- (1-hexamethyleneimino) propyl (diethoxy) methylsilane, ( 1-hexamethyleneimino) methyl (trimethoxy) silane, (1-hexamethyleneimino) methyl (triethoxy) silane, 2- (1-hexamethylenimino) ethyl (triethoxy) silane, 2- (1-hexamethyleneimino) ethyl (trimethoxy) silane, 3- (1-pyrrolidinyl) propyl (triethoxy) silane, 3- (1-pyrrolidinyl) propyl (trimethoxy) silane, 3- (1-heptamethyleneimino) propyl (triethoxy) silane, 3- (1-dodecam ethyleneimino) propyl (triethoxy) silane, 3- (1-hexamethyleneimino) propyl (diethoxy) methylsilane, 3- (1-hexamethyleneimino) propyl (diethoxy) ethylsilane, 1- [3- (triethoxysilyl) propyl] -4,5-dihydroimidazole , 1- [3 - ((diethoxy) methylsilyl) propyl] -4,5-dihydroimidazole, 1- [3- (trimethoxysilyl) propyl] -4,5-dihydroimidazole, 3- [10- (triethoxysilyl) decyl] -4 -oxazoline and the like.

As the alkoxysilane including the imino group, mention should be made of N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine, N- (1,3-dimethylbutylidene) -3- (trimethoxysilyl) -1-propanamine, N - (1,3-dimethylbutylidene) -3- (diethoxy (methyl) silyl) -1-propanamine, N- (1,3-dimethylbutylidene) -3- (dimethoxy (methyl) silyl) -1-propanamine, N- ( 1-methylethylidene) -3- (triethoxysilyl) -1-propanamine, N-ethylidene-3- (triethoxysilyl) -1-propanamine, N- (1-methylpropylidene) -3- (triethoxysilyl) -1-propanamine, N- ( 4-N, N-dimethylaminobenzylidene) -3- (triethoxysilyl) -1-propanamine, N- (cyclohexylidene) -3- (triethoxysilyl) -1-propane min and the like.

For example, as previously described, a modified polymer can be obtained by polymerization using a lithium amide initiator derived from an acyclic secondary amine compound such as diethylamine and the like, or a cyclic secondary amine compound such as hexamethyleneimine and the like, and an organolithium compound , or additionally adding a modifying agent to a polymer solution comprising a lithium active end group resulting from olimerizatsii. It is also preferred that a modified polymer including a functional group introduced into its molecular chain can suppress a decrease in the elastic modulus due to an increase in temperature, but also improve the dispersed state of the filler in a rubber composition containing mixed carbon black or a reinforcing inorganic filler such as dioxide silicon and the like, which provides an effective improvement in low heat during deformation. Specifically, polymers having a branched structure resulting from the use of a multifunctional modifying agent are preferred. In addition, a modified polymer is effectively used, where a tin atom or an organofunctional group, such as an epoxy group, an amino group, a ketimino group, an amido group, an isocyanate group, a thioisocyanate group, a nitrile group and the like, is introduced, especially if carbon black is used together inorganic filler, such as silicon dioxide and the like, as a reinforcing filler.

The rubber component (A) used in the second, third or fourth rubber compositions of the invention contains at least one material selected from natural rubber (NR) and diene-based synthetic rubbers. As the rubber component (A), any of the unmodified and modified rubbers can be used. The diene-based synthetic rubber is preferably synthesized by emulsion polymerization or solution polymerization. As a diene-based synthetic rubber, specifically, polyisoprene rubber (IR), styrene-butadiene copolymer rubber (SBK), polybutadiene rubber (BK), ethylene-propylene-diene rubber (EPDM), chloroprene rubber (CK) should be mentioned isobutylene-isoprene rubber (IIC), halogenated butyl rubber, acrylonitrile-butadiene rubber (NSC) and the like. As the rubber component (A), natural rubber, polyisoprene rubber, styrene-butadiene copolymer rubber, polybutadiene rubber and isobutylene-isoprene rubber are preferred. These rubber components (A) can be used individually or in a mixture of two or more components.

The rubber composition according to the invention preferably contains from 1 to 60 parts by mass, more preferably from 3 to 50 parts by mass, of a low molecular weight conjugated diene polymer (B) based on 100 parts by mass of the rubber component (A). In the case where the amount of admixture of the low molecular weight polymer (B) based on the conjugated diene is less than 1 mass part, the adhesion characteristics of the tire to the road surface on ice and the adhesion characteristics of the tire to the wet road surface cannot be sufficiently improved, while as in the case of exceeding 60 mass parts, the destruction characteristics and the wear resistance of vulcanized rubber are deteriorated. As a result of replacing a portion of the plasticizer with a low molecular weight polymer based on a conjugated diene and limiting the amount of admixed low molecular weight polymer (B) based on a conjugated diene to the above range in the first rubber composition according to the invention, the adhesion characteristics of a tire with a wet road surface are preserved without compromising processability and low rolling resistance, and dry grip performance can be improved.

The low molecular weight polymer (B) based on a conjugated diene in the first rubber composition according to the invention is required to have a weight average molecular weight measured without chain termination as a result of modification by gel permeation chromatography (GPC) and converted to polystyrene of not less than 2000, but less than 150,000. In the event that the weight average molecular weight of the low molecular weight polymer (B) based on the conjugated diene falls within the aforementioned range, a rubber composition can be obtained Ia, the retaining characteristics of the tire grip on wet road surface without deteriorating processability and provides exceptional good balance between the storage modulus of complex elasticity modulus at high temperature and low rolling resistance. Moreover, from the point of view of improving the adhesion characteristics of the tire with the road surface over a wide temperature range from low temperature to high temperature, in addition to various operational characteristics, it is preferable to fall within the range from not less than 2000, but to less than 150,000 , more preferably within the range of 50,000 to 120,000, even more preferably within the range of 50,000 to 100,000.

Since the low molecular weight polymer (B) based on a conjugated diene in the first rubber composition according to the invention is characterized by the presence of at least one functional group and a weight average molecular weight measured without chain termination as a result of modification by gel permeation chromatography (GPC) and converted to polystyrene, not less than 2000, but less than 150,000, low rolling resistance, wear resistance and adhesion characteristics of the tire with the road surface are improved together. Specifically, if the weight average molecular weight of component (B) falls within the range of 2000 to 50,000, preferably within the range of 2000 to 30,000, the flexibility at low temperature and wet grip performance of the tire can be exceptionally well maintained. In addition, in the event that the weight average molecular weight of component (B) falls within the range from not less than 50,000, but to less than 150,000, preferably within the range from 50,000 to 120,000, the storage modulus of the complex elastic modulus is particularly effectively improved at high temperature and low rolling resistance. Therefore, in the case of accentuation of any performance characteristics, including the performance of the tire selected from the characteristics of the adhesion of the tire with a wet road surface, the characteristics of the adhesion of a tire with a dry road surface and intermediate operational characteristics for them, the range of weight average molecular weight of component (B) can be selected depending on accented performance.

The low molecular weight polymer (B) based on a conjugated diene in the first rubber composition according to the invention is required to have a weight average molecular weight measured without chain termination as a result of modification by gel permeation chromatography (GPC) and converted to polystyrene of not less than 2000, but less than 150,000. In the case where the weight average molecular weight, measured without breaking the chain as a result of modification by gel permeation chromatography (GPC) and converted to polystyrene, enters the in the range from 2000 to 50,000, preferably from 2000 to 30,000, the flexibility at low temperature and wet grip performance of the tire can be exceptionally well maintained, while in the case of a weight-average molecular weight of component (B) measured without breaking the chain as a result of the modification and converted to polystyrene, within the range from not less than 50,000, but to less than 150,000, preferably from 50,000 to 120,000, the modulus of storage of the complex elastic modulus is particularly effectively improved at high temperature and low rolling resistance. Therefore, in the case of accentuation of any performance characteristics, including the performance of the tire selected from the characteristics of the adhesion of the tire with a wet road surface, the characteristics of the adhesion of a tire with a dry road surface and intermediate operational characteristics for them, the range of weight average molecular weight of component (B) can be selected depending on accented performance.

A low molecular weight polymer (B) based on a conjugated diene in a third rubber composition according to the invention is required to have a weight average molecular weight measured without chain termination as a result of modification by gel permeation chromatography (GPC) and converted to polystyrene in the range from 2000 to 50,000 , preferably from 2000 to 30000, more preferably from 2000 to 20,000. In the case of using a rubber composition containing an admixed low molecular weight polymer (B) based on a conjugated diene Characterized by the specified range of weight average molecular weight calculated for polystyrene, at least in the region of the ground contact portion of the tire tread can be improved tire traction characteristics with a wet road surface. If a low molecular weight polymer (B) based on a conjugated diene has a weight average molecular weight measured without chain breakage as a result of modification and converted to polystyrene of less than 2000, the fracture resistance will deteriorate, while if it exceeds 50,000, the rubber processability will deteriorate composition. Moreover, if the low molecular weight polymer (B) based on the conjugated diene is a polymer modified using a modifying agent, then upon completion of the modification, the weight average molecular weight, measured by gel permeation chromatography and converted to polystyrene, will preferably be in the range of about 2000 up to 300,000.

The low molecular weight polymer (B) based on a conjugated diene in the fourth rubber composition according to the invention is required to have a weight average molecular weight measured without chain termination as a result of modification by gel permeation chromatography (GPC) and converted to polystyrene of not less than 50,000, but less than 150,000, preferably in the range of 50,000 to 120,000. In the case of using a rubber composition containing an admixed low molecular weight polymer (B) based on a conjugated diene, char which is characterized by the indicated range of weight average molecular weight, converted to polystyrene, at least in the area of contact with the soil of the tread portion of the tire, the storage modulus of the complex elastic modulus (G ') at high temperature and the fracture resistance can be improved. In the case of a weight average molecular weight calculated on polystyrene of less than 50,000, the storage modulus of the complex elastic modulus (G ') of the rubber composition will decrease at high temperature, but there will also be a tendency to increase tan δ, while if it is not less than 150,000, then the processability of the rubber composition will deteriorate.

The low molecular weight polymer (B) based on a conjugated diene in the rubber composition according to the invention contains at least one functional group in its molecule. At present, the conjugated diene-based low molecular weight polymer (B) preferably includes a tin-containing functional group, a silicon-containing functional group, a nitrogen-containing functional group, and the like that are introduced as a result of a modification using a modifying agent such as a tin-containing compound, a silicon-containing compound, a nitrogen-containing compound etc. As a functional group introduced into the low molecular weight polymer (B) based on a conjugated diene, a functional group having an affinity for a filler such as carbon black, silicon dioxide and the like is preferable. Due to the presence of such a functional group, the low molecular weight polymer (B) based on the conjugated diene acquires a higher affinity for the filler in comparison with the case of the absence of a functional group. Thus, the dispersibility of the filler can be improved, which will significantly improve the adhesion characteristics of the tire to the road surface on ice, but the value can also be reduced at high temperature, which will suppress the heating during deformation of the rubber composition itself. Moreover, by adding to the rubber composition a low molecular weight polymer (B) based on a conjugated diene, which includes at least one functional group in its molecule, the storage modulus of the complex elastic modulus (G ') at -20 ° C can be reduced.

There are no particular restrictions on the low molecular weight polymer (B) based on a conjugated diene and it is obtained, for example, by copolymerization using an aromatic vinyl compound and a conjugated diene compound as monomer or homopolymerization using a conjugated diene compound as a monomer. Specifically, polymer (B) can be obtained (1) by a process in which the monomer (s) are polymerized using a polymerization initiator to obtain a (co) polymer comprising an active polymerization center, and then the active polymerization center is modified when using various modifiers, or (2) according to the method for carrying out (co) polymerization of a monomer (s) using a polymerization initiator comprising a functional group. Moreover, these methods can be used in combination. A (Co) polymer comprising an active polymerization center can be obtained by anionic polymerization or coordination polymerization. As the aromatic vinyl compound, mention should be made of styrene, p-methyl styrene, m-methyl styrene, p-tert-butyl styrene, α-methyl styrene, chloromethyl styrene, vinyl toluene and the like. Of these, styrene is preferred. On the other hand, 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethylbutadiene and the like should be mentioned as a conjugated diene compound. Of these, 1,3-butadiene is preferred.

The low molecular weight polymer (B) based on a conjugated diene is preferably a butadiene homopolymer as a homopolymer of a conjugated diene compound or a styrene-butadiene copolymer as a copolymer of an aromatic vinyl compound - a conjugated diene compound. If the low molecular weight polymer (B) based on the conjugated diene is a butadiene homopolymer, then due to the insignificance of the glass transition temperature (Tg), the flexibility at low temperature will be excellent, and the adhesion characteristics of the tire with the road surface on ice will be high. In the case of using a low molecular weight butadiene-based polymer as part of a plasticizer, such as aromatic oil and the like, and mixing it with the composition of the invention, the storage modulus of the complex elastic modulus (G ') in the low temperature region can be reduced and the storage modulus can be increased complex elastic modulus (G ') in the high temperature region, and tan δ in the high temperature region is reduced in combination with low rolling resistance without increasing viscosity Mooney, and in addition, improved fracture characteristics that provide improved wear resistance.

A low molecular weight polymer (B) based on a conjugated diene is required to have an aromatic vinyl compound content of less than 5% by weight. If the aromatic vinyl compound content is less than 5% (wt.), The storage modulus of the complex elastic modulus (G ') at a low temperature can be kept at a low level. In addition, a polymer having a low glass transition temperature (Tg) can improve wear resistance.

The low molecular weight polymer (B) based on a conjugated diene in the portion formed by the conjugated diene is preferably characterized by a vinyl bond content in the range of 0 to 80% (wt.), More preferably 5 to 80% (wt.). If the content of vinyl bonds in the part formed by the conjugated diene compound is exceeded by 80% (wt.), The elastic modulus (especially the accumulation modulus of the complex elastic modulus (G ')) increases significantly at low temperature, which affects the adhesion of the tire to the wet road coated.

In the case of producing a (co) polymer comprising an active polymerization center as a result of anionic polymerization, an alkali metal compound or an alkali metal amide derivative, and more preferably lithium, is preferably used as the polymerization initiator. As the lithium compound, mention is made of hydrocarbyl lithium, a lithium amide compound and the like. In the case of using hydrocarbyl lithium as a polymerization initiator, a (co) polymer is obtained comprising a hydrocarbyl group in the end group initiating the polymerization and an active polymerization center in the other end position. On the other hand, when a lithium amide compound is used as a polymerization initiator, a (co) polymer is obtained comprising a nitrogen-containing functional group in the polymerization-triggering end group and an active polymerization center at a different end position, which can be used as a polymer in the invention (B ) even without modification with a modifying agent. Moreover, the amount of alkali metal compound or alkali metal amide compound used as the polymerization initiator is preferably in the range of 0.2 to 100 mmol per 100 g of monomer.

As hydrocarbyl lithium, ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyllithium, sec-butyl lithium, tert-octyl lithium, n-decyl lithium, phenyl lithium, 2-naphthyl lithium, 2-butyl phenyl lithium, 4-phenyl butyl lithium, cyclohexyl lithium, cyclopent diisopropenylbenzene and butyl lithium and the like. Among them, preferred are alkyl lithium derivatives such as ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, t-octyl lithium, n decyl lithium and the like, and n-butyl lithium is particularly preferred.

On the other hand, lithium hexamethyleneimide, lithium pyrrolidide, lithium piperidide, lithium heptamethyleneimide, lithium dodecamethyleneimide, lithium diethylamide, lithium dipropylamide, lithium diamide, di-diamide lithium ethylhexylamide, lithium didecylamide, lithium N-methylpiperazide, lithium ethylpropylamide, lithium ethylbutylamide, lithium methylbutylamide, lithium ethylbenzylamide, lithium methylphenethylamide, N-lithiomorpholine, N-methyl homopiperazine, N-ethyl homopiperazine, N-ethyl homopiperazine mopiperazin, N-butilgomopiperazin and the like. Among them, cyclic lithium amide compounds such as lithium hexamethyleneimide, lithium pyrrolidide, lithium piperidide, lithium heptamethyleneimide, lithium dodecamethyleneimide and the like are particularly preferred, and lithium hexamethyleneimide and lithium pyrrolidide are particularly preferred. In a preferred embodiment, the lithium amide compound is prepared previously in the presence of a solubilized component (SOL), as described in the patent (SOL patent is cited), or in the absence of a solubilized component, as described in the patent (patent citing limiting the structure of the amine without using SOL), and then it can be used as a polymerization initiator. Moreover, the lithium amide compound can be obtained in the polymerization system (in situ (locally)) without prior refinement for use as a polymerization initiator, as described in the patent (InSitu patent is cited).

A low molecular weight polymer based on a conjugated diene (B) comprising at least one nitrogen-containing functional group selected from the group consisting of a substituted amino group described by formula (II) and a cyclic amino group described by formula (III) can be obtained in the result of using as a lithium amide compound a lithium amide compound represented by a substituted amino group described by the following formula (II):

,

,

where R ² is independently an alkyl group containing carbon atoms in an amount of from 1 to 12, a cycloalkyl group or an aralkyl group,

or a cyclic amino group described by the following formula (III):

,

,

where R ³ represents an alkylene group comprising 3-16 methylene groups, a substituted alkylene group (where the substituent is a C1-C16 hydrocarbon group), an oxyalkylene group or an N-alkylaminoalkylene group, and may or may not exist between carbon atoms in alkylene groups there are stitches. In yet another example, a nitrogen-containing functional group can be introduced by using a urea compound such as DMI (1,3-dimethyl-2-imidazolidinone), NMP (N-methylpyrrolidone) and the like; a ketone compound substituted with a dialkylamino group such as DEAB (4,4'-bis (diethylamino) benzophenone) and the like; an aldehyde compound substituted with a dialkylamino group such as diethylaminobenzaldehyde and the like; a compound containing a C = N double bond, such as a Schiff base compound and the like; a compound comprising an isocyanate group, a compound comprising a thioisocyanate group, and the like. More preferably, it is a functional group obtained by carrying out a reaction between a chain termination modifying agent selected from a hydrocarbyloxysilane compound having a nitrogen-containing substituent and a polymer comprising a terminal group active in the polymerization (living polymer). Moreover, it can be introduced by reaction with a polymerizable vinyl compound or a conjugated diene compound comprising a nitrogen-containing functional group such as 2-vinylpyridine, 4- (N, N-dimethylamino) methyl styrene and the like.

In formula (II), R ² represents an alkyl group containing 1-12 carbon atoms, a cycloalkyl group or an aralkyl group, and more specifically, preferably include a methyl group, an ethyl group, a butyl group, an octal group, a cyclohexyl group, 3-phenyl A -1-propyl group, an isobutyl group and the like. Moreover, R ² may be identical or different.

In the formula (III), R ³ represents an alkylene group comprising 3-16 methylene groups, a substituted alkylene group, an oxyalkylene group or an N-alkylaminoalkylene group. There may or may not be crosslinking between carbon atoms. Currently, a substituted alkylene group includes alkylene groups ranging from monosubstituted to octasubstituted, and a linear or branched alkyl group containing 1-12 carbon atoms, a cycloalkyl group, a bicycloalkyl group, an aryl group and an aralkyl group should be mentioned as a substituent. Specifically, as R ³ , a trimethylene group, a tetramethylene group, a hexamethylene group, an oxydiethylene group, an N-alkyl azadiethylene group such as an N-methyl back-ethylene group, an N-butyl azadiethylene group and the like, dodecamethylene group, hexadecamethylene group and the like are preferable.

The lithium amide compound can be preliminarily obtained from a secondary amine and a lithium compound and used in a polymerization reaction or can be obtained in a polymerization system. As the secondary amine may be mentioned dimethylamine, diethylamine, dibutylamine, dioctylamine, dicyclohexylamine, diisobutylamine, and the like as well as cyclic amines such as pyrrolidine, piperidine, azacycloheptane (i.e. hexamethyleneimine), N-methyl homopiperazine, N-butilgomopiperazin, morpholine, dodekametilenimin 2- (2-ethylhexyl) pyrrolidine, 3- (2-propyl) pyrrolidine, 3,5-bis (2-ethylhexyl) piperidine, 4-phenylpiperidine, 7-decyl-1-azacyclotridecan, 3,3-dimethyl-1 -azacyclotetradecane, 4-dodecyl-1-azacyclooctane, 4- (2-phenylbutyl) -1-azacyclooctane, 3-ethyl-5-cy Clohexyl-1-azacycloheptane, 4-hexyl-1-azacycloheptane, 9-isoamyl-1-azacycloheptadecane, 2-methyl-1-azacycloheptadec-9-ene, 3-isobutyl-1-azacycododecane, 2-methyl-7-tert- butyl-1-azacyclododecane, 5-nonyl-1-azacyclododecane, 8- (4'-methylphenyl) -5-pentyl-3-azabicyclo [5.4.0] undecane, 1-butyl-6-azabicyclo [3.2.1] octane , 8-ethyl-3-azabicyclo [3.2.1] octane, 1-propyl-3-azabicyclo [3.2.2] nonane, 3- (tert-butyl) -7-azabicyclo [4.3.0] nonane, 1.5 , 5-trimethyl-3-azabicyclo [4.4.0] decane and the like. Alternatively, the aforementioned hydrocarbyl lithium can be used as a lithium compound.

There are no particular restrictions on the method for producing a low molecular weight polymer based on a conjugated diene (B) using the aforementioned polymerization initiator. For example, polymer (B) can be obtained by polymerizing monomer (s) in a hydrocarbon solvent which is inactive with respect to the reaction polymerization. As a hydrocarbon solvent inactive with respect to the polymerization reaction, mention should be made of propane, n-butane, isobutane, n-pentane, isopentane, n-hexane, cyclohexane, propene, 1-butene, isobutene, trans-2-butene, cis-2 butene, 1-pentene, 2-pentene, 1-hexene, 2-hexene, benzene, toluene, xylene, ethylbenzene and the like. They can be used individually or in combination of two or more components.

Anionic polymerization can be carried out in the presence of a randomizer. The randomizer can adjust the microstructure of the part formed by the conjugated diene compound in the copolymer, and more specifically, has an effect that regulates the level of vinyl bonds in the copolymer of the part formed by the conjugated diene compound, which ensures random distribution of the conjugated diene compound and aromatic vinyl link in the copolymer connections and so on. As the randomizer, dimethoxybenzene, tetrahydrofuran, dimethoxyethane, diethylene glycol dibutyl ether, diethylene glycol dimethyl ether, bistetrahydrofurylpropane, triethylamine, pyridine, N-methylmorpholine, N, N, N-di-tetra-di-di-tetramethylene potassium tert-butoxide, sodium tert-amylate and the like. The amount of randomizer used is preferably in the range of 0.01 to 100 molar equivalents per 1 mol of polymerization initiator.

Anionic polymerization is preferably carried out by a solution polymerization method. The concentration of monomer in the polymerization reaction solution is preferably in the range from 5 to 50% (wt.), More preferably from 10 to 30% (wt.). Moreover, in the case of the combined use of a conjugated diene compound and an aromatic vinyl compound, the content of the aromatic vinyl compound in the monomer mixture is preferably not more than 80% (wt.), More preferably not more than 5% (wt.), And can be appropriately selected depending on the level of aromatic vinyl compound in the target copolymer. In addition, there are no particular restrictions on the polymerization system, and it may be a periodic system or a continuous system.

The polymerization temperature during anionic polymerization is preferably in the range from 0 to 150 ° C, more preferably from 20 to 130 ° C. In addition, the polymerization can be carried out at a pressure of the feed line of the gaseous feedstock, but preferably it is usually carried out at a pressure sufficient to maintain the monomers used in a substantially liquid state. In the case of carrying out the polymerization reaction at a pressure higher than the pressure of the feed line of the gaseous feedstock, the pressure in the reaction system is preferably created using an inert gas. Moreover, the feedstock materials used in the polymerization, such as monomers, a polymerization initiator, a solvent, and the like, are preferably used after preliminary removal of reaction inhibitors such as water, oxygen, carbon dioxide, proton compounds and the like.

In the case of modifying the active polymerization center of the (co) polymer, including the active polymerization center, with a modifying agent, a nitrogen-containing compound, a silicon-containing compound and a tin-containing compound are preferably used as the modifying agent. In this case, a nitrogen-containing functional group, a silicon-containing functional group or a tin-containing functional group can be introduced as a result of the modification reaction.

The nitrogen-containing compound used as the modifying agent is essentially the same as those described for the modifier of the chain termination reaction used in the rubber component (A), and specifically, preferably it includes a substituted or unsubstituted amino group, an amido group , an imino group, an imidazole group, a nitrile group or a pyridyl group. A nitrogen-containing compound suitable for use as a modifying agent includes isocyanate compounds such as diphenylmethanediisocyanate, crude MDI, trimethylhexamethylene diisocyanate, tolylene diisocyanate and the like, 4- (dimethylamino) benzophenone, 4- (diethylamino-4-benzenephenone) 4-dimethylamino-benzenephenone dimethylaminobenzylidenebutylamine, dimethylimidazolidinone, N-methylpyrrolidone and the like.

In addition, the silicon-containing compound used as the modifying agent is essentially the same as those described for the modifying agent of the chain termination reaction used in the rubber component (A). Moreover, specifically, preferred are the hydrocarbyloxy silane compound described by the following formula (IV):

where A is a monovalent group containing at least one functional group selected from the groups of (thio) epoxy, (thio) isocyanate, (thio) ketone, (thio) aldehyde, imine, amide, isocyanuric acid triester, hydrocarbyl complex (thio) carboxylic acid ester, (thio) carboxylic acid metal salt, carboxylic anhydride, carboxylic acid halide, carbonic acid dihydrocarbyl ester, cyclic tertiary amine, acyclic tertiary amine, nitrile, pyridine, sulfide and m ltisulfida; R ⁴ represents a single bond or a divalent inactive hydrocarbon group; R ⁵ and R ⁶ independently represent a monovalent aliphatic hydrocarbon group containing 1-20 carbon atoms, or a monovalent aromatic hydrocarbon group containing 6-18 carbon atoms; n is an integer of 0-2; in the case of several OR ⁶ groups, they may be identical or different; and the active proton and onium salt are not included in the molecule,

and its incomplete condensate,

as well as a hydrocarbyloxy silane compound described by the following formula (V):

,

,

where R ⁷ and R ⁸ independently represent a monovalent aliphatic hydrocarbon group containing carbon atoms in an amount of 1-20, or a monovalent aromatic hydrocarbon group containing carbon atoms in an amount of 6-18; p is an integer of 0-2; in the case of several OR ⁸ groups, they may be identical or different; and the active proton and onium salt are not included in the molecule,

and its incomplete condensate.

Among the functional groups in A in the formula (IV), the imine includes ketimine, aldimine and amidine, and the (thio) carboxylic acid ester includes an unsaturated carboxylic acid ester such as acrylate, methacrylate and the like, and the acyclic tertiary amine includes N, An N-disubstituted aromatic amine, such as N, N-disubstituted aniline and the like, and a cyclic tertiary amine may include a thio ether as part of the ring. As the metal in the metal salt of (thio) carboxylic acid, alkali metal, alkaline earth metal, Al, Sn, Zn and the like can be mentioned.

As a divalent inert hydrocarbon group in R ⁴ , an alkylene group containing 1-20 carbon atoms is preferred. The alkylene group may be straight, branched or cyclic, but a straight chain is particularly preferred. As the direct alkylene group, methylene group, ethylene group, trimethylene group, tetramethylene group, pentamethylene group, hexamethylene group, octamethylene group, decamethylene group, dodecamethylene group and the like are mentioned.

As R ⁵ and R ⁶ mention should be made of an alkyl group containing carbon atoms in an amount of 1-20, an alkenyl group containing carbon atoms in an amount of 2-18, an aryl group containing carbon atoms in an amount of 6-18, an aralkyl group containing atoms carbon in an amount of 7-18, and the like. In this case, the alkyl group and alkenyl group can be straight, branched or cyclic and include, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, hexyl group, octal group, decyl group, dodecyl group, cyclopentyl group, cyclohexyl group, vinyl group, propenyl group, allyl group, hexenyl group, octenyl group, cyclopent an enyl group, a cyclohexenyl group and the like. In addition, the aryl group may have a substituent on the aromatic ring, such as a lower alkyl group and the like, and includes, for example, a phenyl group, a tolyl group, a xylyl group, a naphthyl group and the like. Furthermore, the aralkyl group in the aromatic ring may have a substituent, such as a lower alkyl group and the like, and includes, for example, a benzyl group, a phenethyl group, a naphthylmethyl group and the like.

In formula (IV), n is an integer of 0-2, and is preferably 0. Moreover, it is required that the active proton and the onium salt are not included in the molecule.

In the case of a hydrocarbyloxy silane compound represented by the formula (IV), for example a hydrocarbyloxy silane compound including a (thio) epoxy group, mention may be made, for example, 2-glycidoxyethyltrimethoxysilane, 2-glycidoxyethyltriethoxymethyloxytropyloxymethyloxy-methoxy-3-methoxydryloxy-3-methoxydryloxy-3-methoxydryloxy-3-methoxy-dimethyloxy-methoxy-dimethoxy-methoxy-dimethyloxy-methoxy-dimethyloxy-methoxy-dimethoxy-methoxy-dimethoxy-methoxy-dimethoxy-dimethoxy-methoxy-dimethoxy-methoxy-dimethoxy-methoxy-dimethoxy-methoxy-dimethoxy , (3-glycidoxypropyl) methyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl (methyl) dimethoxysil n and compounds resulting from substitution of the epoxy group in these compounds thioepoxy. Among them, 3-glycidoxypropyltrimethoxysilane and 3-glycidoxypropyltriethoxysilane are particularly preferred.

As the hydrocarbyloxy silane compound including an imino group, N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine, N- (1-methylethylidene) -3- (triethoxysilyl) -1-propanamine, N can be mentioned -ethylidene-3- (triethoxysilyl) -1-propanamine, N- (1-methylpropylidene) -3- (triethoxysilyl) -1-propanamine, N- (4-N, N-dimethylaminobenzylidene) -3- (triethoxysilyl) -1 -propanamine, N- (cyclohexylidene) -3- (triethoxysilyl) -1-propanamine, as well as trimethoxysilyl compounds, methyldiethoxysilyl compounds, ethyldiethoxysilyl compounds, methyldimethoxysilyl co of the connections, and similar compounds etildimetoksisililnye triethoxysilyl compounds corresponding data. Of these, N- (1-methylpropylidene) -3- (triethoxysilyl) -1-propanamine and N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine are particularly preferred.

As the compound comprising the imine (amidine) group, mention should be made of 1- [3- (triethoxysilyl) propyl] -4,5-dihydroimidazole, 1- [3- (trimethoxysilyl) propyl] -4,5-dihydroimidazole, N- ( 3-triethoxysilylpropyl) -4,5-dihydroimidazole, N-zopropoxysilylpropyl) -4,5-dihydroimidazole, N- (3-methyldiethoxysilylpropyl) -4,5-dihydroimidazole and the like. Among them, N- (3-triethoxysilylpropyl) -4,5-dihydroimidazole is preferred.

As the compound comprising the carboxylic acid ester group, mention may be made of 3-methacryloyloxypropyltriethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, 3-methacryloyloxypropyltriisopropoxysilane and the like. Among them, 3-methacryloyloxypropyltrimethoxysilane is preferred.

As the compound comprising the isocyanate group, mention is made of 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropylmethyldiethoxysilane, 3-isocyanatopropyltriisopropoxysilane and the like. Among them, 3-isocyanatopropyltriethoxysilane is preferred.

As the compound comprising carboxylic acid anhydride, mention should be made of 3-triethoxysilyl propyl succinic anhydride, 3-trimethoxysilyl propyl succinic anhydride, 3-methyldiethoxysilyl propyl succinic anhydride and the like. Among them, 3-triethoxysilyl propyl succinic acid anhydride is preferred.

As a hydrocarbyloxy silane compound including a cyclic tertiary amino group, mention should be made of 3- (1-hexamethyleneimino) propyl (triethoxy) silane, 3- (1-hexamethyleneimino) propyl (trimethoxy) silane, (1-hexamethyleneimino) methyl (trimethoxy) silane, 1-hexamethyleneimino) methyl (triethoxy) silane, 2- (1-hexamethyleneimino) ethyl (triethoxy) silane, 2- (1-hexamethyleneimino) ethyl (trimethoxy) silane, 3- (1-pyrrolidinyl) propyl (triethoxy) silane, 3 - (1-pyrrolidinyl) propyl (trimethoxy) silane, 3- (1-heptamethyleneimino) propyl (triethoxy) silane, 3- (1-dodecamethyleneimino) propyl ( rietoksi) silane, 3- (1-hexamethyleneimino) propyl (diethoxy) methylsilane, 3- (1-hexamethyleneimino) propyl (diethoxy) etilsilan, 3- [10- (triethoxysilyl) decyl] -4-oxazoline and the like. Among these, 3- (1-hexamethyleneimino) propyl (triethoxy) silane and (1-hexamethyleneimino) methyl (trimethoxy) silane are preferred.

As a hydrocarbyloxy silane compound including an acyclic tertiary amino group, mention should be made of 3-dimethylaminopropyl (triethoxy) silane, 3-dimethylaminopropyl (trimethoxy) silane, 3-diethylaminopropyl (triethoxy) silane, 3-diethylaminopropyl (trimethoxy) silane, 2-dimethyl silane, 2-dimethylaminoethyl (trimethoxy) silane, 3-dimethylaminopropyl (diethoxy) methylsilane, 3-dibutylaminopropyl (triethoxy) silane and the like. Among these, 3-diethylaminopropyl (triethoxy) silane and 3-dimethylaminopropyl (triethoxy) silane are preferred.

As another hydrocarbyloxysilane compound, mention is made of 2- (trimethoxysilylethyl) pyridine, 2- (triethoxysilylethyl) pyridine, 2-cyanoethyltriethoxysilane and the like.

The hydrocarbyloxysilane compounds described by formula (IV) can be used individually or in combination of two or more components. In addition, an incomplete condensate of the hydrocarbyloxy silane compound may be used.

In the formula (V), R ⁷ and R ⁸ are the same as those mentioned for R ⁵ and R ⁶ in the formula (IV), respectively.

As the hydrocarbyloxysilane compound represented by the formula (V), mention may be made, for example, tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetraisopropoxysilane, tetra-n-butoxysilane, tetraisobutoxysilane, tetra-sec-butoxysilane, tetra-sec-butoxysilane, tetra-sec-butoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltriisopropoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, propyltriethoxysilane, butyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, dimetidomethoxysilane lfenildimetoksisilan, vinyltrimethoxysilane, vinyltriethoxysilane, divinildimetoksisilan, divinildietoksisilan and the like.

Among them, tetraethoxysilane is particularly preferred.

The hydrocarbyloxysilane compounds described by formula (V) can be used individually or in combination of two or more components. In addition, an incomplete condensate of the hydrocarbyloxy silane compound may be used.

The tin-containing compound or silicon-containing compound used as a modifying agent is preferably a coupling reaction agent represented by the following formula (I):

,

,

where R ¹ independently selected from the group consisting of an alkyl group containing carbon atoms in an amount of 1-20, a cycloalkyl group containing carbon atoms in an amount of 3-20, an aryl group containing carbon atoms in an amount of 6-20, and an aralkyl group, containing carbon atoms in an amount of 7-20; Z represents tin or silicon; X independently represents chlorine or bromine; and a is 0-3, ab is 1-4, provided that a + b = 4. As a result of the modification using the coupling reaction agent represented by the formula (I), the cold flow resistance of the polymer (B) can be improved. Moreover, the polymer (B) obtained by the modification using the coupling reaction agent represented by formula (I) contains at least one bond selected from a tin-carbon bond and a silicon-carbon bond.

Specifically, as R ¹ in the formula (I), mention should be made of a methyl group, an ethyl group, an n-butyl group, an informal group, a cyclohexyl group, an n-octyl group, a 2-ethylhexyl group and the like. In addition, specifically, as a coupling reaction agent represented by the formula (I), SnCl ₄ , R ¹ SnCl ₃ , R ¹ ₂ SnCl ₂ , R ¹ ₃ SnCl, SiCl ₄ , R ¹ SiCl ₃ , R ¹ ₂ are preferred SiCl ₂ , R ¹ ₃ SiCl and the like, and SnCl ₄ and SiCl ₄ are particularly preferred.

The reaction of modifying the active polymerization center using the aforementioned modifying agent is preferably carried out according to the reaction method in solution. The monomer (s) used in the polymerization may be included in such a solution. In addition, during the modification reaction, no special restrictions are imposed on the reaction system, and it may be a periodic system or a continuous system. In addition, no special restrictions are imposed on the reaction temperature during the modification reaction until the reaction proceeds, and the temperature at which the polymerization reaction is carried out can be used as such temperature. The amount of modifying agent used is preferably in the range of 0.25 to 3.0 mol, more preferably 0.5 to 1.5 mol, per 1 mol of polymerization initiator used to produce the (co) polymer.

In the invention, the reaction solution containing the polymer (B) can be dried to separate the polymer (B), and then the resulting polymer (B) can be mixed with the rubber component (A), or the reaction solution containing the polymer (B) ) can be mixed with the rubber solution formed by the rubber component (A) in the solution state, and then dried to obtain a mixture of the rubber component (A) and the polymer (B).

The first rubber composition according to the invention must necessarily contain a filler (C), while the second, third and fourth rubber compositions according to the invention preferably contain a filler (C). In addition, in the rubber compositions corresponding to the invention, selected in the range from the first to the fourth, the filler (C) is preferably included in an amount in the range from 20 to 100 mass parts, based on 100 mass parts of the rubber component (A). If the rubber compositions according to the invention are selected in the range from the first to the fourth mixed filler (C) in an amount of less than 20 parts by mass, the fracture characteristics and the wear resistance of the vulcanized rubber will be insufficient, while if they are exceeded 100 parts by mass there will be a trend towards a deterioration in processability. In addition, in the rubber composition according to the invention, a content of from 30 to 90 parts by weight of filler (C) is calculated more preferably per 100 parts by weight of the rubber composition (A). As filler (C), carbon black and silicon dioxide are preferably used. Moreover, carbon black of the FEF, SRF, HAF, ISAF and SAF grades is preferably used as carbon black, and HAF, ISAF and SAF carbon black is more preferred. On the other hand, precipitated silica, colloidal silica and the like are preferably used as silica, and precipitated silica is more preferred. These reinforcing fillers can be used individually or in combination of two or more components. In the case of containing in the rubber composition according to the invention, as the filler (C) of silica, the amount of silica admixed is preferably not less than 10 parts by mass, more preferably in the range of 10 to 80 parts by mass, based on 100 parts by mass rubber composition (A).

In addition, the rubber composition corresponding to the invention may contain a plasticizer (F). As a plasticizer (F), process oils such as paraffin oil, naphthenic oil, aromatic oil and the like should be mentioned. Aromatic oil is preferred in terms of fracture characteristics and wear resistance, and naphthenic oil and paraffin oil are preferred in terms of low deformation heating and low temperature characteristics. There are no particular restrictions on the amount of admixed plasticizer, but the total amount of admixed low molecular weight polymer (B) based on a conjugated diene and plasticizer (F) is preferably in the range from 5 to 80 parts by mass, more preferably from 5 to 60 parts by mass, when calculated on 100 mass parts of the rubber component (A). If the combined amount of admixed polymer (B) and plasticizer (F) falls within the aforementioned range, degradation of the vulcanized rubber fracture performance can be suppressed. If the plasticizer (F) contains in the rubber composition according to the invention, the proportion of the low molecular weight polymer (B) based on the conjugated diene in the total amount of the low molecular weight polymer (B) based on the conjugated diene and plasticizer (F) is preferably not less than 20% ( wt.).

In the third rubber composition according to the invention, the extractability in chloroform for the case of extraction in chloroform within 48 hours after vulcanization is completed is preferably not less than 60% (wt.) Based on the total weight of the admixed low molecular weight polymer (B) based on the conjugated diene . On the other hand, in the fourth rubber composition according to the invention, the extractability in chloroform for the case of extraction in chloroform for 48 hours upon completion of vulcanization is preferably not more than 60% (wt.), More preferably not more than 40% (wt. .), based on the total mass of admixed low molecular weight polymer (B) based on a conjugated diene. At present, the extractability in chloroform (% (wt.)) Is the ratio of the mass of extracted polymer (B) to the total mass of admixed polymer (B) as measured after the vulcanized rubber obtained by vulcanizing the rubber composition was extracted in chloroform for 48 hours.

The second, third and fourth rubber compositions according to the invention contain cavities in their rubber matrix. In the invention, a rubber composition containing cavities in its rubber matrix is obtained, for example, by combining and rolling a conventional rubber mixture and a foaming agent (G) and curing the resulting rubber composition under ordinary foaming conditions of the foaming agent (G), to thereby generate gas. The proportion of cavities (Vs) in the rubber composition is preferably in the range of 5 to 35%. In the case of a fraction of cavities of less than 5%, the adhesion characteristics of the tire to the road surface on ice will deteriorate, while if it exceeds 35%, there will be a tendency to deteriorate the fracture and wear characteristics. The cavities included in the second to fourth rubber compositions of the invention are preferably expandable cavities, but they may be cavities that result from the decomposition of hollow particles, cavities that result from elution of hydrophilic particles, or cavities that result from falling away crumbling foreign substances.

The fraction of cavities (Vs) (%) can be calculated using the following equation (VI):

where ρ ₁ is the density of the rubber composition (g / cm ³ ), ρ ₀ is the density of the part formed in the rubber composition by the solid phase (g / cm ³ ), and ρ _g is the density of the part formed in the rubber composition by the cavities, (g / cm ³ ). Since the value of ρ _g in the part formed by the cavities is negligible, the fraction of cavities (Vs) (%) can be calculated using the following equation (VII):

.

.

As the foaming agent (G) used in the rubber composition according to the invention, mention should be made of azodicarbonamide (ADCA), dinitrosopentamethylenetetraamine (DPT), dinitrosopentastyrene tetraamine, a benzenesulfonylhydrazide derivative, p, p'-hydroxybisbenzene sulfonic bicarbonyl dicarbonyl bicarbonyl sulfonyl bicarbonate, bicarbonyl sulfonyl bicarbonate, sodium, ammonium carbonate, nitrososulfonylase compound generating nitrogen, N, N'-dimethyl-N, N'-dinitrosophthalamide, toluenesulfonyl hydrazide or its derivative, p-toluenesulfonylsemicarb azide, p, p'-oxybisbenzenesulfonylsemicarbazide and the like. Among these blowing agents (G), azodicarbonamide (ADCA), dinitrosopentamethylene tetraamine (DPT) and the like are preferable from the viewpoint of manufacturability in production. These blowing agents (G) can be used individually or in combination of two or more components.

There are no particular restrictions on the form of the foaming agent (G), and for any purpose it can be appropriately selected from a dispersed form, a liquid form, and the like. The form of the foaming agent (G) can be observed using, for example, a microscope. The average particle size of the dispersed foaming agent (G) can be measured using, for example, a Coulter counter and the like.

To the rubber composition of the invention, the foaming agent (G) is preferably mixed in an amount in the range of 1 to 20 parts by mass, more preferably 2 to 10 parts by mass, based on 100 parts by mass of the rubber component (A).

In addition, the foaming agent (G) is preferably used in conjunction with urea, zinc stearate, zinc benzenesulfinate, zinc white and the like as an additive to promote foaming. These foaming aids can be used individually or in combination of two or more components. The foaming reaction is promoted by the joint use of an additive that promotes foaming, which increases the degree of reaction approaching its completion, as a result of which temporary unnecessary deterioration in quality parameters can be suppressed.

In addition to the aforementioned rubber component (A), a low molecular weight polymer (B) based on a conjugated diene, a filler (C), a plasticizer (F), a foaming agent (G) and a foaming aid, the rubber composition of the invention can suitably additives commonly used in the rubber industry, such as an antioxidant, a silane sizing agent, a vulcanization accelerator, a vulcanization accelerating agent, a vulcanizing agent and the like within a volume, are mixed, not harmful to achieve the objectives of the invention. As these additives, those that are commercially available may preferably be used. The rubber composition can be obtained by admixing to the rubber component (A) a low molecular weight polymer (B) based on a conjugated diene and, if necessary, appropriately selected other additives and rolling, heating, extruding and the like.

The rubber composition of the invention is preferably a rubber composition for manufacturing a tire.

The pneumatic tire of the invention is characterized by the use of a rubber composition in a tire member. As a tire element, a tread part, a side part, a part formed by a filler cord of a collar, a part formed by a rubberized layer of a tire carcass reinforcing a rubber part for a deflated tire and the like are to be mentioned. Specifically, in the pneumatic tire of the invention, the aforementioned rubber composition is preferably used at least in the area of contact with the ground of the tread portion. A tire using a rubber composition at least in the area of contact with the ground of the tread portion is characterized by excellent low fuel consumption, a storage modulus of the complex elastic modulus (G ') at high temperature, fracture resistance, wet grip characteristics and grip characteristics road tires on ice. On the pneumatic tire according to the invention, no particular restrictions are imposed as long as the above-mentioned rubber composition is used, and it can be obtained by the usual method. Moreover, ordinary air or air characterized by a regulated partial pressure of oxygen, but also inert gases such as nitrogen, argon, helium and the like can be used as the gas filling the tire.

EXAMPLES

The following examples are provided to illustrate the invention and are not intended to limit it.

Example 1 to obtain the polymer (A)

In a 800 ml glass pressure vessel dried and purged with nitrogen, a solution of butadiene in cyclohexane (16%) and a solution of styrene in cyclohexane (21%) are loaded so as to obtain a content of butadiene monomer of 40 g and a content of styrene monomer of 10 g, and thereafter, 0.12 mmol of 2,2-ditetrahydrofurylpropane is charged and 0.4 mmol of n-butyllithium (n-BuLi) is additionally added, and then a polymerization reaction is carried out in a warm water bath at 50 ° C. for 1.5 hours. In this case, the degree of conversion during polymerization is approximately 100%. Then, to terminate the polymerization reaction, 0.5 ml of a solution of 2,6-di-tert-butyl-p-cresol (BHT (butylated hydroxytoluene)) in isopropanol (BHT concentration: 5% by weight) is added to the polymerization system, and then drying is carried out in accordance with a conventional method and polymer (A-1) is obtained. The resulting high molecular weight styrene-butadiene copolymer (polymer (A-1)) is characterized by a content of bound styrene of 20% (wt.), A content of vinyl bonds of 58% and a weight average molecular weight (Mw) without chain termination as a result of modification of 290000. These measurement methods are described below.

Example 2 to obtain the polymer (A)

In a 800 ml glass pressure vessel dried and purged with nitrogen, a solution of butadiene in cyclohexane (16%) and a solution of styrene in cyclohexane (21%) are loaded so as to obtain a content of butadiene monomer of 40 g and a content of styrene monomer of 10 g, and thereafter, 0.12 mmol of 2,2-ditetrahydrofurylpropane is charged and 0.4 mmol of n-butyllithium (n-BuLi) is additionally added, and then a polymerization reaction is carried out in a warm water bath at 50 ° C. for 1.5 hours. In this case, the degree of conversion during polymerization is approximately 100%. Then, 0.1 mmol of tin tetrachloride is added to the polymerization system as a modifying agent, and an additional reaction is carried out for 30 minutes at 50 ° C. Then, to terminate the polymerization reaction, 0.5 ml of a solution of 2,6-di-tert-butyl-p-cresol (BHT) in isopropanol (concentration of BHT: 5% (wt.)) Is added to the polymerization system, and then drying is carried out in in accordance with the usual method and get the polymer (A-2). The resulting high molecular weight styrene-butadiene copolymer (polymer (A-2)) is characterized by a content of bound styrene of 20% (wt.), A content of vinyl bonds of 58% and a weight average molecular weight (Mw) without chain termination as a result of modification of 290000. These measurement methods are described below.

Example 3 to obtain the polymer (A)

The polymer (A-3) is obtained by the same method as in Production Example 2, with the exception of replacing n-butyllithium with lithium hexamethyleneimide. The resulting high molecular weight styrene-butadiene copolymer (polymer (A-3)) is characterized by a content of bound styrene of 20% (wt.), A content of vinyl bonds of 58% and a weight average molecular weight (Mw) without chain termination as a result of modification of 290000.

Example 4 to obtain the polymer (A)

The polymer (A-4) is obtained by the same method as in Production Example 2, with the exception of replacing 0.1 mmol of tin tetrachloride with 0.4 mmol of dimethylimvdazolidinone. The resulting high molecular weight styrene-butadiene copolymer (polymer (A-4)) is characterized by a content of bound styrene of 20% (wt.), A content of vinyl bonds of 58% and a weight average molecular weight (Mw) without chain termination as a result of modification of 290000.

Example 1 to obtain the polymer (B)

Obtaining low molecular weight polybutadiene (polymers (B)), demonstrating the physical characteristics shown in table 2-4, is carried out as follows (except when using lithium hexamethyleneimide (GMI-Li) as the polymerization initiator).

300 g of cyclohexane and 50 g of 1,3-butadiene are loaded into a 800 ml pressure-operated glass container dried and purged with nitrogen, and then ditetrahydrofurylpropane is charged so as to obtain a quantitative ratio of ditetrahydrofurylpropane / n-butyllithium 0.03. After the subsequent addition of 3.6 mmol of n-butyllithium (n-BuLi), a polymerization reaction is carried out for 5 hours at 50 ° C. In this case, the degree of conversion during polymerization is approximately 100%. After that, various modifiers are immediately added to the polymerization system and, for an additional 30 minutes, a modification reaction is carried out at 50 ° C. In this case, the modifier / n-BuLi (molar ratio) is tin tetrachloride / n-BuLi = 0.22 (molar ratio) when using tin tetrachloride, tetraethoxysilane / n-BuLi = 0.9 (molar ratio) when using tetraethoxysilane, "crude" MDI / n-BuLi = 0.9 (molar ratio) in the case of using "raw" MDI and S340 / h-BuLi = 0.9 (molar ratio). Then, to terminate the polymerization reaction, 0.5 ml of a solution of 2,6-di-tert-butyl-p-cresol (BHT) in isopropanol (concentration of BHT: 5% (wt.)) Is added to the polymerization system, and then drying is carried out in in accordance with the usual method and receive each modified low molecular weight polybutadiene. Moreover, in the case where the modification reaction is not carried out, low molecular weight polybutadiene is obtained in a similar manner, with the exception of the corresponding reaction.

Example 2 for the preparation of polymer (B)

The polymerization reaction is carried out in the same manner as in Example 1 for the preparation of polymer (B), with the exception of replacing the polymerization catalyst from Example 1 for the preparation of polymer (B) n-butyllithium (n-BuLi) with 3.6 mmol of lithium hexamethyleneimide (GMI) -Li). Upon completion of the polymerization reaction, the modification reaction is not carried out, and to terminate the polymerization reaction, 0.5 ml of a solution of 2,6-di-tert-butyl-p-cresol (BHT) in isopropanol is added to the polymerization system (BHT concentration: 5% (wt.) ), and then carry out the drying in accordance with the usual method and get low molecular weight polybutadiene.

The weight average molecular weight (Mw) and the microstructure of the low molecular weight polybutadiene obtained in Examples 1-2 of the preparation of the polymer (B) are measured in accordance with the following methods. The results are shown in tables 2-4.

(1) Weight average molecular weight (Mw)

The weight average molecular weight (Mw) of each polymer without chain termination by modification when converted to polystyrene is measured by gel permeation chromatography [GPC: HLC-8020, manufactured by TOSOH, column: GMH-XL (two serial columns), manufactured by TOSOH, detector : differential refractometer (refractive index)] when using monodispersed polystyrene as standard.

(2) Microstructure and bound styrene content

The polymer microstructure is determined by the infrared method (Morello method), and the content of bound styrene in the polymer is determined by the integral ratio in the ¹ H-NMR spectrum.

After that, using polymers (A-1) - (A-4) and polymers (B) obtained in Production Examples 1-2, a rubber composition is obtained corresponding to the formulation of the mixture shown in Table 1, and then for 15 minutes vulcanization is carried out at 160 ° C. until vulcanized rubber is obtained, and in accordance with the following methods, the accumulation modulus of the complex elastic modulus (G '), the loss tangent (tan δ) and the extractability in chloroform are measured for the thus vulcanized rubber. The results are shown in tables 2-4.

(3) The storage modulus of the complex elastic modulus (G ')

The storage modulus of the complex elastic modulus (G ') is measured at temperatures of -20 ° C and 50 ° C, a frequency of 15 Hz and a strain of 1% using a device for measuring viscoelasticity manufactured by RHEOMETRICS Corporation, and is described by the index obtained under the assumption that that the storage modulus of the complex elastic modulus (G ') for the rubber composition of comparative example 1 is 100. As for the storage modulus of the complex elastic modulus (G') at 50 ° C, the larger the index value, the greater the storage modulus integrated polices modulus. On the other hand, with regard to the storage modulus of the complex elastic modulus (G ') at −20 ° C., the smaller the index value, the more improved the flexibility at low temperature.

(4) Loss tangent (tan δ)

The loss tangent (tan δ) is measured at temperatures of 0 ° C and 50 ° C, a frequency of 15 Hz and a strain of 1% using a viscoelasticity measuring device manufactured by RHEOMETRICS Corporation, and is described by the index obtained under the assumption that the angle tangent loss (tan δ) for the rubber composition of comparative example 1 is 100. With regard to the tangent of the loss angle (tan δ) at 50 ° C, the lower the index value, the more improved will be the low heating during deformation. On the other hand, with regard to the loss tangent (tan δ) at 0 ° C, the larger the index value, the more improved the adhesion characteristics of the tire to the wet road surface.

(5) Extractability in chloroform

A vulcanized rubber sample is extracted within 48 hours in a Soxhlet extractor using chloroform as a solvent, and the fraction of the extracted polymer (B) in the total weight of the admixed polymer (B) (% (wt.)) Is calculated from the remainder of the vulcanized rubber sample.

Table 1 Mixed quantity (mass parts) Rubber component (A) BK * 1 fifty SBC * 2 fifty Polymer (B) * 3 fifteen Carbon black * 4 27 Silica * 5 27 Silane Sizing * 6 2.5 Aromatic oil 5 Stearic acid 2 Antioxidant 6C * 7 one Zinc White 3 DFG vulcanization accelerator * 8 0.8 Vulcanization accelerator DM * 9 one Vulcanization Accelerator NS * 10 one Sulfur 1,5 * 1 "BR01", manufactured by JSR Corporation, 1,4-polybutadiene, characterized by a high content of cis units, weight average molecular weight = 600,000. * 2 Type of polymers (A-1) - (A-4) are shown in tables 2-3. * 3 Polymer (B) obtained in Production Example 1 or 2. * 4 Seast KH (trademark, N339), manufactured by Tokai Carbon Co., Ltd. * 5 Nipsil AQ (trademark), manufactured by TOSOH Silica Co., Ltd. * 6 Si 69 (trademark), manufactured by Degussa Corporation, bis (3 triethoxysilylpropyl) tetrasulfide. * 7 N- (1,3-dimethylbutyl) -N'-phenyl-p-phenylenediamine. * 8 Diphenylguanidine. * 9 Dibenzothiazyl disulfide. * 10 N-tert-butyl-2-benzothiazyl sulfenamide.

As can be seen from table 2, in the case of srednevekovoi molecular weight, measured without breaking the chain as a result of modification, not less than 2000, but less than 150000 (examples 1-15), the storage modulus of the complex elastic modulus at - 20 ° C can be reduced without decreasing the loss tangent at 0 ° C, and, in addition, the loss tangent at 50 ° C can also be reduced.

As can be seen from tables 3 and 4, the effect of the invention is obtained even if the type of modifying agent is replaced with a nitrogen-containing compound or a silicon-containing compound. In the case of modifying the rubber component (A), the storage modulus of the complex elastic modulus at -20 ° C can be further reduced, and the loss tangent at 50 ° C can also be reduced.

An example of a polymer (B-1)

300 g of cyclohexane and 50 g of 1,3-butadiene are charged into a 800 ml pressure-dried glass container dried and purged with nitrogen, and then 5.28 mmol of n-butyllithium (n-BuLi) is added and then over 2 hours at 50 ° C, a polymerization reaction is carried out. In this case, the degree of conversion during polymerization is approximately 100%. Then, to terminate the polymerization reaction, 0.5 ml of a solution of 2,6-di-tert-butyl-p-cresol (BHT) in isopropanol (concentration of BHT: 5% (wt.)) Is added to the polymerization system, and then drying is carried out in in accordance with the usual method and get the polymer (B-1).

An example of the preparation of polymers (B-2) - (B-4)

300 g of cyclohexane and 50 g of 1,3-butadiene are charged into a 800 ml pressure-dried glass container dried and purged with nitrogen, and then 5.28 mmol of n-butyllithium (n-BuLi) is added and then over 2 hours at 50 ° C, a polymerization reaction is carried out. In this case, the degree of conversion during polymerization is approximately 100%. After that, the modifier shown in table 4 is immediately added to the polymerization system in the amount shown in table 4 as a modifying agent, and a modification reaction is carried out for an additional 30 minutes at 50 ° C. Then, to terminate the polymerization reaction, 0.5 ml of a solution of 2,6-di-tert-butyl-p-cresol (BHT) in isopropanol (concentration of BHT: 5% by weight) is added to the polymerization system, and then drying is carried out in In accordance with the usual method, polymers (B-2) - (B-4) are obtained.

An example of a polymer (B-5)

The polymer (B-5) is obtained by the same method as the polymer (B-1), with the exception of using 5.28 mmol of lithium hexamethyleneimide obtained in sito instead of n-butyllithium (n-BuLi) [GMI -Li; the molar ratio of hexamethyleneimine (GMI) / lithium (Li) = 0.9], when expressed through the equivalent of lithium.

An example of a polymer (B-6)

The polymer (B-6) is obtained by the same method as the polymer (B-2), except for the use of 5.28 mmol of lithium hexamethyleneimide obtained in sito instead of n-butyllithium (n-BuLi) as an initiator of polymerization [GMI -Li; the molar ratio of hexamethyleneimine (GMI) / lithium (Li) = 0.9], when expressed through the equivalent of lithium.

The weight average molecular weight (Mw), microstructure, and bound styrene content of polymers (B-1) to (B-6) prepared as described previously are measured in accordance with the above methods. The results are shown in table 5.

Table 5 Polymer (B-1) Polymer (B-2) Polymer (B-3) Polymer (B-4) Polymer (B-5) Polymer (B-6) Polymerization initiator Type of n-BuLi n-BuLi n-BuLi n-BuLi GMI-Li * 12 GMI-Li * 12 Type of - MDI * 13 THO * 11 S340 * 15 - THO * 11 Modifier Amount Used (mmol) - 0.22 0.9 0.9 - 0.22 The content of bound styrene (% (wt.)) 0 0 0 0 0 0 The content of vinyl bonds (%) twenty twenty twenty twenty twenty twenty Weight average molecular weight (Mw) 20 × 10 ³ 20 × 10 ³ 20 × 10 ³ 20 × 10 ³ 20 × 10 ³ 20 × 10 ³ * 11 Titanium tetrachloride. * 12 Lithium hexamethyleneimide. * 13 Raw MDI, MR400, manufactured by Nippon Urethane Corporation. * 15 N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanediamine.

An example of a polymer (B-7)

300 g of cyclohexane and 50 g of 1,3-butadiene are charged into an 800 ml glass container, dried and purged with nitrogen, under pressure, and then 1.06 mmol of n-butyl lithium (n-BuLi) is added, and then over 2 hours at 50 ° C carry out the polymerization reaction. In this case, the degree of conversion during polymerization is approximately 100%. Then, to terminate the polymerization reaction, 0.5 ml of a solution of 2,6-di-tert-butyl-p-cresol (BHT) in isopropanol (concentration of BHT: 5% (wt.)) Is added to the polymerization system, and then drying is carried out in in accordance with the usual method and get the polymer (B-7).

An example of a polymer (B-8)

300 g of cyclohexane and 50 g of 1,3-butadiene are charged into a 800 ml pressurized glass container, dried and purged with nitrogen, and then 1.06 mmol of n-butyllithium (n-BuLi) is added and then over 2 hours at 50 ° C carry out the polymerization reaction. In this case, the degree of conversion during polymerization is approximately 100%. Then, 0.22 mmol of tin tetrachloride (SnCl ₄ ) is immediately added to the polymerization system as a modifying agent, and a further modification reaction is carried out for 30 minutes at 50 ° C. In this case, the degree of conversion during polymerization is approximately 100%. Then, to terminate the polymerization reaction, 0.5 ml of a solution of 2,6-di-tert-butyl-p-cresol (BHT) in isopropanol (concentration of BHT: 5% (wt.)) Is added to the polymerization system, and then drying is carried out in in accordance with the usual method and get the polymer (B-8).

An example of a polymer (B-9)

The polymer (B-9) is obtained by the same method as the polymer (B-8), with the exception of using 1.06 mmol of lithium hexamethyleneimide obtained locally as the polymerization initiator instead of n-butyl lithium (n-BuLi) [ GMI-Li; the molar ratio of hexamethyleneimine (GMI) / lithium (Li) = 0.9] when expressed through the equivalent of lithium.

An example of a polymer (B-10)

The polymer (B-10) is obtained by the same method as the polymer (B-8), except for using instead of 50 g of 1,3-butadiene 45 g of 1,3-butadiene and 5 g of styrene, and, in addition, 0.53 mmol of ditetrahydrofurylpropane is added.

An example of obtaining polymers (B-11) - (B-12)

Polymers (B-11) - (B-12) are obtained in the same manner as polymers (B-8) - (B-9), except for using tin tetrachloride instead of 0.9 mmol tetraethoxysilane.

An example of a polymer (B-13)

The polymer (B-13) is obtained by the same method as the polymer (B-8), with the exception of using instead of tin tetrachloride 0.9 mmol N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1- propanediamine (S340).

The weight average molecular weight (Mw), microstructure, and bound styrene content of polymers (B-7) to (B-13) prepared as described previously are measured in accordance with the above methods. The results are shown in table 6.

Table 6 Polymer (B-7) Polymer (B-8) Polymer (B-9) Polymer (B-10) Polymer (B-11) Polymer (B-12) Polymer (B-13) Polymerization initiator n-BuLi n-BuLi GMI-Li n-BuLi n-BuLi n-BuLi n-BuLi Modifier - SnCl ₄ SnCl ₄ - Tetraethoxysilane Tetraethoxysilane S340 The content of bound styrene (% (wt.)) 0 0 0 10 0 10 0 The content of vinnel bonds (%) twenty twenty twenty 60 twenty 60 twenty Weight average molecular weight (Mw) 10 × 10 ⁴ 10 × 10 ⁴ 10 × 10 ⁴ 10 × 10 ⁴ 10 × 10 ⁴ 10 × 10 ⁴ 10 × 10 ⁴

After that, using polymers (B-1) - (B-6), a rubber composition is obtained corresponding to the formulation of the mixture shown in Table 7, and then vulcanization is carried out under normal conditions to obtain vulcanized rubber. For the resulting vulcanized rubber, the fraction of cavities is calculated according to the above equation (VII) and the extractability in chloroform is measured in accordance with the above method, and the storage modulus of the complex elastic modulus (G '), tan δ and tensile strength are measured in accordance with following methods. The results are shown in table 8.

(6) Tensile Strength

According to JIS K6301-1995, a tensile test is carried out at room temperature and the tensile strength is measured, which is described by the index obtained under the assumption that the tensile strength for the rubber composition of comparative example 5 is 100. The larger the value index, the better will be the resistance to destruction.

(7) The storage modulus of the complex elastic modulus (G ')

The storage modulus of the complex elastic modulus (G ') is measured at a temperature of -20 ° C, a frequency of 10 Hz and a strain of 0.1% using a device for measuring viscoelasticity manufactured by RHEOMETRICS Corporation, and is described by an index obtained under the assumption that the number the inverse of the storage modulus of the complex elastic modulus (G ') for the rubber composition of comparative example 5 is 100. The higher the index value, the lower the storage modulus of the complex elastic modulus, and the better the adhesion characteristics of the tire with road surface on ice.

(8) tan δ

The tan δ value is measured under conditions of a frequency of 10 Hz, a strain of 0.1% and a temperature of 0 ° C using a viscoelasticity measuring device manufactured by RHEOMETRICS Corporation, and is described by the index obtained under the assumption that the tan δ value for a rubber composition of Comparative Example 5 is 100. The higher the index value, the better the wet grip performance of the tire.

Table 7 Mixed quantity (mass parts) Rubber component (A) Natural rubber * 17 60 Polybutadiene rubber * 18 40 Polymer (B) * 19 twenty DPT / urea * 20 5.7 Carbon black N220 60 Stearic acid 1,5 Zinc White 1,5 Antioxidant 6C * 21 one Vulcanization accelerator DM * 22 0.2 Vulcanization accelerator CZ * 23 0.5 Sulfur one * 17 Molecular mass of 2,000,000. * 18 "BR01", manufactured by JSR Corporation, 1,4-polybutadiene, characterized by a high content of cis units, a molecular weight of 600,000. * 19 Polymers (B-1) - (B-6) obtained in accordance with the above methods. The type of polymer used is shown in table 8. * 20 Dinitrosopentamethylene tetraamine (DPT): urea = 1: 1 (mass ratio). * 21 N- (1,3-dimethylbutyl) -N-phenyl-p-phenylenediamine. * 22 Di-2-benzothiazolyl disulfide. * 23 N-cyclohexyl-2-benzothiazolylsulfenamide.

Table 8 Comparator
ny example 5 Example 20 Example 21 Example 22 Example 23 Example 24 Type of polymer used (B) IN 1 IN 2 IN 3 AT 4 AT 5 AT 6 Cavity fraction % twenty twenty twenty twenty twenty twenty Fracture resistance Tensile strength Index one hundred 103 103 103 102 104 Characteristics
road tire clutch on ice Accumulation module complex
modulus of elasticity (G ') (- 20 ° С) Index one hundred 115 117 118 113 122 Characteristics
wet grip tire clutch (0 ° C) Index one hundred 98 98 97 99 97 Extractability in chloroform % (wt.) 81 78 79 78 74 70

As can be seen from table 8, in comparison with the rubber composition of comparative example 5 using a polymer (B-1), the rubber compositions of examples 20-24 using polymers (B-2) - (B-6) containing molecules of at least one functional group exhibit excellent adhesion characteristics of the tire to the road surface on ice due to a significant decrease in the storage modulus of the complex elastic modulus (G ') at -20 ° C. In addition, it should be understood that due to the effect of improving the dispersibility of the filler due to the use of polymers (B-2) - (B-6) in the rubber compositions of the examples, the tensile strength is improved.

After that, using polymers (B-7) - (B-10) or aromatic oil, a rubber composition is obtained corresponding to the formulation of the mixture shown in Table 9, and then vulcanization is carried out for 15 minutes at 160 ° C. until vulcanized rubber is obtained. For the resulting vulcanized rubber, the fraction of cavities is calculated according to the above equation (VII) and the extractability in chloroform is measured according to the above method, and the tensile strength, the storage modulus of the complex elastic modulus (G ') and tan δ are measured in accordance with following methods. The results are shown in table 10.

(9) Tensile Strength

According to JIS K6301-1995, a tensile test is carried out at room temperature and the tensile strength is measured, which is described by the index obtained under the assumption that the tensile strength for the rubber composition of comparative example 6 is 100. The larger the value index, the better will be the resistance to destruction.

(10) The storage modulus of the complex elastic modulus (G ')

The storage modulus of the complex elastic modulus (G ') at a temperature of -20 ° C or 50 ° C is measured under conditions of a frequency of 15 Hz and a strain of 1.0% using a device for measuring viscoelasticity manufactured by RHEOMETRICS Corporation. The storage modulus of the complex elastic modulus (G ') at −20 ° C is described by the index obtained under the assumption that the number inverse to the storage modulus of the complex elastic modulus (G') for the rubber composition of comparative example 6 is 100. The higher the index value the better grip characteristics of the tire on the ice. On the other hand, the storage modulus of the complex elastic modulus (G ') at 50 ° C is described by the index obtained under the assumption that the storage modulus of the complex elastic modulus (G') for the rubber composition of comparative example 6 is 100. The larger the index value, the better the storage modulus of the complex elastic modulus (G ') at high temperature.

Table 9 Mixed quantity (mass parts) Rubber component (A) Natural rubber * 17 60 Polybutadiene rubber * 18 40 Aromatic oil or polymer (B) * 24 twenty DPT / urea * 20 5.7 Carbon black (N220) 60 Stearic acid 1,5 Zinc White 1,5 Antioxidant 6C * 21 one Vulcanization accelerator DM * 22 0.2 Vulcanization accelerator CZ * 23 0.5 Sulfur one * 17 Molecular mass of 2,000,000. * 18 "BR01", manufactured by JSR Corporation, 1,4-polybutadiene, characterized by a high cis-3 content, molecular weight of 600,000. * 20 Dinitrosopentamethylene tetraamine (DPT): urea = 1: 1 (mass ratio). * 21 N- (1,3-dimethylbutyl) -N-phenyl-p-phenylenediamine. * 22 Di-2-benzothiazolyl disulfide. * 23 N-cyclohexyl-2-benzothiazolylsulfenamide. * 24 Aromatic oil or polymer type [polymers (B-7) - (B-10)] are shown in Table 10.

Table 10 Reference Example 6 Reference Example 7 Example 25 Example 26 Example 27 Aromatic oil or polymer type (B) Aromatic oil AT 7 AT 8 AT 9 AT 10 Cavity fraction % twenty twenty twenty twenty twenty Resist
destruction Tensile strength Index one hundred 108 112 111 110 Characteristics
road clutch tires on ice G '(-20 ° C) Index one hundred 103 114 119 101 The storage modulus of the complex modulus of elasticity at high temperature G '(50 ° C) Index one hundred 123 120 118 128 Extractability in chloroform % (wt.) 85 38 32 thirty 35

As can be seen from table 10, in comparison with the rubber composition of comparative example 6 using aromatic oil, the rubber compositions of examples 25-26 and comparative examples 7-8 using polymers (B-7) - (B-10), characterized the specified weight average molecular weight, demonstrate good tensile strength and the storage modulus of the complex elastic modulus (G ') at -20 ° C and 50 ° C and give the tire excellent fracture resistance and adhesion characteristics of the tire to the road surface per liter do while maintaining accumulation unit complex elastic modulus (G ') at high temperature. In addition, in comparison with the rubber compositions of comparative examples 7-8, the rubber compositions of examples 25-26 as a result of the use of polymers (B-8) - (B-9) containing at least one functional in their molecules group, the modulus of accumulation of the complex modulus of elasticity (G ') is significantly reduced at -20 ° C and, the adhesion characteristics of the tire with the road surface on ice become excellent.

Further, when using polymers (B-7), (B-11), (B-10) and (B-13), a rubber composition is obtained corresponding to the formulation of the mixture shown in Table 11, and then for 15 minutes at 160 ° C carry out the vulcanization to obtain vulcanized rubber. For the resulting vulcanized rubber, the fraction of cavities is calculated according to the above equation (VII) and the extractability in chloroform is measured in accordance with the above method, and the tensile strength, the storage modulus of the complex elastic modulus (G ') and tan δ are measured in accordance with following methods. The results are shown in table 11.

(11) Tensile Strength

According to JIS K6301-1995, a tensile test is carried out at room temperature and the tensile strength is measured, which is described by the index obtained under the assumption that the tensile strength for the rubber composition of comparative example 9 is 100. The higher the index value the better the fracture resistance.

(12) The storage modulus of the complex elastic modulus (G ')

The storage modulus of the complex elastic modulus (G ') is measured at a temperature of -20 ° C, a frequency of 10 Hz and a strain of 0.1% when using a device for measuring viscoelasticity manufactured by RHEOMETRICS Corporation, and is described by the index obtained under the assumption that the module the accumulation of the complex modulus of elasticity (G ') for the rubber composition of comparative example 9 is 100. The lower the index value, the better the adhesion characteristics of the tire to the road surface on ice.

(13) tan δ

The tan δ value is measured under conditions of a frequency of 10 Hz, a strain of 0.1% and a temperature of 0 ° C using a viscoelasticity measuring device manufactured by RHEOMETRICS Corporation, and is described by the index obtained under the assumption that the tan δ value for a rubber composition of Comparative Example 9 is 100. The higher the index value, the better the wet grip performance of the tire.

Table 11 Reference Example 9 Example 27 Example 28 Reference Example 10 Rubber component Natural rubber * 25 Mass part 40 40 40 40 (BUT) Polybutadiene * 26 60 60 60 60 Carbon black SAF 25 25 25 25 Silicon dioxide * 27 40 40 40 40 Silane Sizing * 28 4.0 4.0 4.0 4.0 Stearic acid 2.0 2.0 2.0 2.0 Low molecular weight
conjugated diene polymer (B) AT 7 fifteen - - - AT 11 - fifteen - - Recipe AT 10 - - - fifteen making up the mixture B-13 - - fifteen - Zno 2.0 2.0 2.0 2.0 Antioxidant IFFD * 29 2.5 2.5 2.5 2.5 MBTS vulcanization accelerator * 30 0.6 0.6 0.6 0.6 CBS vulcanization accelerator * 31 1,5 1,5 1,5 1,5 Sulfur 1,5 1,5 1,5 1,5 DPT / urea * 32 5.7 5.7 5.7 5.7 The proportion of cavities (%) twenty twenty twenty twenty Fracture resistance, tensile strength (index) one hundred 105 104 110 Traction on ice on the ice, G '(- 20 ° C) (index) one hundred 121 119 88 Wet grip characteristics, (0 ° C) (index) one hundred 99 98 120 Extractability in chloroform 69 67 65 67 * 25 RSS # 1, molecular weight 2,000,000. * 26 Cis-1,4-polybutadiene, UBEPOL BR150L (trade name), manufactured by UBE Industries, Ltd, molecular weight 500,000. * 27 Nipsil AQ (trade name), manufactured by Nippon Silica Industrial * 28 Si 69 (trade name), manufactured by Degussa Corporation. * 29 N-isopropyl-N-phenyl-p-phenylenediamine. * 30 Dibenzothiazyl disulfide. * 31 N-cyclohexyl-2-benzothiazole sulfenamide. * 32 Dinitrosopentamethylene tetraamine (DPT): urea = 1: 1 (mass ratio).

As can be seen from table 11, pneumatic tires using the rubber compositions of examples 27-28, demonstrate excellent adhesion characteristics of tires with wet road surface and adhesion characteristics of tires with road surface on ice, and in addition, durability.

<Example of polymer production (B-14)>

300 g of cyclohexane and 48.5 g of 1,3-butadiene and 1.5 g of styrene are charged into an 800 ml glass container, dried and purged with nitrogen, and, in addition, 5.28 mmol of n-butyllithium (n -BuLi), and then a polymerization reaction is carried out for 2 hours at 50 ° C. In this case, the degree of conversion during polymerization is approximately 100%.

Then, 0.22 mmol of crude MDI (MR400 manufactured by Nippon Urethane Corporation) was added to the polymerization system for additionally carrying out the modification reaction over 30 minutes at 50 ° C.

Then, to terminate the polymerization reaction, 0.5 ml of a solution of 2,6-di-tert-butyl-p-cresol (BHT) in isopropanol (concentration of BHT: 5% (wt.)) Is added to the polymerization system, and then drying is carried out in in accordance with the usual method and get the polymer (B-14).

The weight average molecular weight (Mw), microstructure, and bound styrene content of the resulting polymer (B-14) are measured in accordance with the methods described in paragraphs [0123] and [0124] of the present description of the invention. The results are shown in the following table A.

Table a Polymer (B-14) Polymerization initiator Type of n-BuLi Modifier Type of MDI Amount Used (mmol) 0.22 The level of the content of bound styrene (% (wt.)) 3 The content of vinyl bonds (%) twenty Weight average molecular weight (Mw) 20 × 10 ³

After that, when using polymer (B-14), a rubber composition is obtained corresponding to the formulation of the mixture shown in the following Table B, and then vulcanization is carried out under normal conditions to obtain vulcanized rubber.

Table B Mixed quantity (mass parts) Rubber component (A) Natural rubber * 17 60 Polybutadiene rubber * 18 40 Polymer (B-14) twenty DPT / urea * 20 5.7 Carbon black N220 60 Stearic acid 1,5 Zinc White 1,5 Antioxidant 6C * 21 one Vulcanization accelerator DM * 22 0.2 Vulcanization accelerator CZ * 23 0.5 Sulfur one * 17 Molecular mass of 2,000,000. * 18 "BR01", manufactured by JSR Corporation, 1,4-polybutadiene, characterized by a high content of cis units, a molecular weight of 600,000. * 20 Dinitrosopentamethylene tetraamine (DPT): urea = 1: 1 (mass ratio). * 21 N- (1,3-dimethylbutyl) -N'-phenyl-p-phenylenediamine. * 22 Di-2-benzothiazolyl disulfide. * 23 N-cyclohexyl-2-benzothiazolylsulfenamide.

For the resulting vulcanized rubber, the fraction of cavities is calculated in accordance with equation (VII) disclosed in the description of the invention, and the extractability in chloroform is measured in accordance with the method disclosed in paragraph [0128] of the present description of the invention, and the storage modulus of the complex elastic modulus (G '), tan δ and tensile strength are measured in accordance with the methods disclosed in paragraphs [0153] - [0155] of the present description of the invention. The results are shown in the following table C.

Table C Additional Example A Type of polymer used (B) B-14 Cavity fraction % twenty Resistance Tensile strength Index 105 destruction tensile Traction on Ice The storage modulus of the complex elastic modulus (G ') (-20 ° C) Index 110 Wet grip characteristics tan δ (0 ° C) Index 101 Extractability in chloroform % (wt.) 76

Claims (38)

1. A rubber composition characterized by admixing a low molecular weight polymer (B) based on a conjugated diene, characterized by the presence of at least one functional group, an aromatic vinyl compound content of from 0 to less than 5% (wt.) And a weight average molecular weight measured without clipping chains as a result of modification by gel permeation chromatography and recalculated to polystyrene, not less than 2000, but less than 150,000, and filler (C) to the high molecular weight rubber component (A), character erizuyuschemusya weight average molecular weight, measured without an open circuit as a result of modification by gel permeation chromatography and calculated for polystyrene of not less than 150,000, and their vulcanization,
the polymer (B) is obtained by (co) polymerizing the monomers with a polymerization initiator to obtain a (co) polymer having an active polymerization center, followed by modification of the active polymerization center with a modifying agent, the functional group in the low molecular weight polymer (B) based on a conjugated diene is at least one selected from the group consisting of a tin-containing functional group, a silicon-containing functional group, and a nitrogen-containing functional group, wherein the nitrogen-containing The expanding functional group is obtained from at least one nitrogen-containing compound selected from the group consisting of isocyanate compounds, thioisocyanate compounds, aminobenzophenone compounds, urea derivatives, ketimine or aldimine compounds containing a C = NC bond, and cyclic amide compounds. 2. The rubber composition obtained by admixing a low molecular weight polymer (B) based on a conjugated diene, characterized by the presence of at least one functional group, an aromatic vinyl compound content of from 0 to less than 5% (wt.) And a weight average molecular weight measured without breaking the chain as a result of modification by gel permeation chromatography and recalculated to polystyrene, not less than 2000, but less than 150,000, and foaming agent (G) to the rubber component (A) formed by at least one material selected from natural rubber and diene-based synthetic rubbers, characterized by a weight average molecular weight, measured without breaking the chain as a result of gel permeation chromatography modification and converted to polystyrene of not less than 150,000, and their vulcanization, characterized by inclusion cavities in the rubber matrix of the rubber composition. 3. The rubber composition according to claim 2, where the low molecular weight polymer (B) based on a conjugated diene is characterized by a weight average molecular weight measured without chain termination as a result of modification by gel permeation chromatography and converted to polystyrene in the range of 2000-50000. 4. The rubber composition according to claim 2, where the low molecular weight polymer (B) based on a conjugated diene is characterized by a weight average molecular weight measured without chain termination as a result of modification by gel permeation chromatography and converted to polystyrene not less than 50,000, but less than 150,000. 5. The rubber composition according to claim 3, where the extractability in chloroform for the case of extraction in chloroform for 48 hours after completion of vulcanization is not less than 60% (wt.) When calculating the total weight of the admixed low molecular weight polymer (B) based on conjugated diene . 6. The rubber composition according to claim 4, where the extractability in chloroform for the case of extraction in chloroform for 48 hours after completion of vulcanization is not less than 60% (wt.) When calculating the total weight of the admixed low molecular weight polymer (B) based on conjugated diene . 7. The rubber composition according to claim 1 or 2, where the low molecular weight polymer (B) based on a conjugated diene is included in an amount of from 1 to 60 parts by weight. when calculated on 100 parts by weight rubber component (A). 8. The rubber composition according to claim 1 or 2, where the low molecular weight polymer (B) based on a conjugated diene in the part formed by the conjugated diene compound is characterized by a vinyl content in the range from 5 to 80% (wt.). 9. The rubber composition according to claim 1 or 2, wherein the low molecular weight polymer (B) based on a conjugated diene is a butadiene homopolymer or a styrene-butadiene copolymer. 10. The rubber composition according to claim 1 or 2, where the low molecular weight polymer (B) based on a conjugated diene is a polymer that is obtained by modifying its active polymerization center using a tin-containing compound, a silicon-containing compound or a nitrogen-containing compound. 11. The rubber composition according to claim 10, where the tin-containing compound or silicon-containing compound are modifying agents of the chain termination reaction represented by the following formula (I):

where R ¹ independently selected from the group consisting of an alkyl group containing carbon atoms in an amount of from 1 to 20, a cycloalkyl group containing carbon atoms in an amount of from 3 to 20, an aryl group containing carbon atoms in an amount of from 6 to 20, and an aralkyl group containing carbon atoms in an amount of from 7 to 20;
Z represents tin or silicon;
X independently represents chlorine or bromine;
a is 0-3 and
b is 1-4 provided that a + b = 4. 12. The rubber composition of claim 10, where the nitrogen-containing functional group is selected from the group consisting of a substituted amino group represented by the following formula (II):

where R ² independently represents an alkyl group containing carbon atoms in an amount of from 1 to 12, a cycloalkyl group or an aralkyl group, and a cyclic amino group represented by the following formula (III):

where R ³ represents an alkylene group containing 3-16 methylene groups, a substituted alkylene group, an oxyalkylene group or an N-alkylaminoalkylene group. 13. The rubber composition of claim 10, where the silicon-containing functional group is a functional group derived from hydrocarbyloxysilane. 14. The rubber composition according to claim 1, where the low molecular weight polymer (B) based on a conjugated diene is characterized by a weight average molecular weight measured without chain termination as a result of modification by gel permeation chromatography and converted to polystyrene of not less than 20,000, but less than 150,000. 15. The rubber composition according to 14, where the low molecular weight polymer (B) based on a conjugated diene is characterized by a weight average molecular weight measured without chain termination as a result of gel permeation chromatography modification and converted to polystyrene in the range of 50,000-120000. 16. The rubber composition according to claim 3, where the low molecular weight polymer (B) based on a conjugated diene is characterized by a weight average molecular weight measured without chain termination as a result of modification by gel permeation chromatography and converted to polystyrene in the range of 2000-30000. 17. The rubber composition according to claim 4, where the low molecular weight polymer (B) based on a conjugated diene is characterized by a weight average molecular weight measured without chain termination as a result of modification by gel permeation chromatography and converted to polystyrene in the range of 50,000-120000. 18. The rubber composition according to claim 1 or claim 2, which further comprises from 20 to 100 parts by weight filler (C) based on 100 parts by weight rubber component (A). 19. The rubber composition according to p. 18, which contains from 30 to 90 parts by weight filler (C) based on 100 parts by weight rubber composition (A). 20. The rubber composition according to claim 1 or 2, where the filler (C) are carbon black and / or silicon dioxide. 21. The rubber composition according to claim 1 or 2, which contains not less than 10 parts by weight silica based on 100 parts by weight rubber component (A). 22. The rubber composition according to claim 1, where the rubber component (A) contains at least one material selected from the group consisting of a copolymer (D) of an aromatic vinyl compound, a conjugated diene compound, a polymer (E) of a conjugated diene compound, and natural rubber. 23. The rubber composition according to claim 22, wherein the copolymer (D) of the aromatic vinyl compound - conjugated diene compound is a styrene-butadiene copolymer. 24. The rubber composition according to claim 22, wherein the polymer (E) of the conjugated diene compound is a butadiene homopolymer. 25. The rubber composition according to item 22, where each material selected from a copolymer (D) of an aromatic vinyl compound - a conjugated diene compound and a polymer (E) of a conjugated diene compound, contains at least one functional group. 26. The rubber composition according A.25, where the functional group in the copolymer (D) of an aromatic vinyl compound - a conjugated diene compound and a polymer (E) of a conjugated diene compound is at least a group selected from the group consisting of tin-containing functional group , a silicon-containing functional group and a nitrogen-containing functional group. 27. The rubber composition according to claim 1 or 2, where the total amount of admixed low molecular weight polymer (B) based on a conjugated diene and plasticizer (F) is in the range from 5 to 80 parts by weight when calculated on 100 parts by weight rubber component (A). 28. The rubber composition according to item 27, where the total amount of admixed low molecular weight polymer (B) based on a conjugated diene and plasticizer (F) is in the range from 5 to 60 parts by weight per 100 parts by weight rubber component (A). 29. The rubber composition according to item 27, where the proportion of low molecular weight polymer (B) based on conjugated diene in the total amount of low molecular weight polymer (B) based on conjugated diene and plasticizer (F) is not less than 20% (wt.). 30. The rubber composition according to claim 2, where the proportion of cavities in the rubber composition is from 5 to 35%. 31. The rubber composition according to p. 30, which is obtained by mixing from 1 to 20 wt.h. the foaming agent (G) per 100 parts by weight rubber component (A), followed by vulcanization and foaming. 32. The rubber composition according to claim 30, wherein the foaming agent (G) is at least one selected from the group consisting of azodicarbonamide, dinitrosopentamethylene tetraamine, azobisisobutilonitrile, toluenesulfonyl hydrazide and a toluenesulfonyl hydrazide derivative. 33. The rubber composition according to one of claims 1 to 32, which is a rubber composition intended for the manufacture of tires. 34. The pneumatic tire element, characterized in using the rubber composition according to p. 33 in the tire element. 35. The tire element according to clause 34, where the tire element is at least one selected from the group consisting of a tread part, a side part, a part formed by a filler cord of the flange, a part formed by a rubberized layer of the tire carcass, and reinforcing rubber parts for tires with deflated pressure. 36. An element of a pneumatic tire, characterized in using the rubber composition according to claim 33, at least in the area of contact with the ground of the tread portion. 37. The tire element according to clause 36, which is an element of a studless tire. 38. The tire element according to clause 37, which is an element of a studless tire for a passenger car.