JP2015131926A - Rubber composition and tire prepared using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rubber composition comprising carbon black, without loss of the characteristics of a natural rubber, making it possible to give a pneumatic tire comprising the natural rubber with rolling resistance and wear resistance improved at high levels, and a tire prepared using the same.SOLUTION: This invention relates to a rubber composition in which, a rubber component is a modified conjugated diene polymer and a natural rubber for use is a product of the hydrolysis of a phospholipid, for example, the hydrolysis by lipase and/or phospholipase enzyme treatment, and high hydrogen carbon black is also blended with the rubber composition. This invention also relates to a tire prepared using the rubber composition.

Description

  The present invention relates to a rubber composition and a tire using the rubber composition.

  Conventionally, natural rubber and synthetic rubber have been widely used in many fields such as industrial equipment such as tires, rubber belts, rubber rolls, priders, fenders, and sports equipment such as tennis balls, basketballs, soccer balls, and volleyballs. Recently, it has been frequently used in the medical field and the bio field. Further, in tires, it is used as a material for all components constituting rubber tires such as treads, sidewalls, ply coating rubbers, and bead fillers.

In recent years, as natural rubber, it has been proposed to improve the properties of natural rubber by subjecting natural rubber latex to chemical treatment and enzyme treatment to decompose or remove components other than rubber components contained in natural rubber. .
For example, the total amount of nitrogen in natural rubber is chemically reduced (for example, see Patent Document 1) or reduced by using a proteolytic enzyme (for example, see Patent Document 2 and Patent Document 3). Proposed.
However, natural rubber with a stable quality cannot be obtained by simply enzymatically treating natural rubber, and a stable quality with respect to a natural rubber composition after the secondary product of natural rubber and its products can be easily obtained. I couldn't.

  In general, a reinforcing filler is added to the rubber component, but as a synthetic rubber, a modified conjugated diene polymer introduced with a functional group having a high affinity with the reinforcing filler is used as the rubber component. . The modified conjugated diene polymer is a modified polymer in which a functional group is introduced by reacting a compound having a specific functional group with the active site of the conjugated diene polymer having an active site. A modified condensation polymer obtained by conducting a condensation reaction involving the functional group in the presence of a condensation accelerator comprising a compound of an element belonging to at least one of Group 4, Group 12, Group 13, Group 14 and Group 15. Proposed.

  Further, in the reinforcing filler, the particle size and structure of carbon black blended in the rubber composition constituting the tire are the dominant factors for improving the wear resistance of the tire. As the particle size of the carbon black is reduced, the wear resistance is improved. However, it is known that when the particle size of the carbon black is extremely small, poor dispersion occurs in the rubber and the exothermic property of the rubber increases. When a tire tread is produced with such a rubber composition, it is excellent in abrasion resistance but inferior in fuel efficiency. That is, the wear resistance and the low heat build-up are in a trade-off relationship with the carbon black particle size. However, wear resistance and low heat build-up are mutually contradictory properties, and carbon blacks having various properties have been proposed to solve this problem.

  In order to improve such performance, the applicant of the present application has proposed high-hydrogen carbon black as a carbon black for rubber compounding (see, for example, Patent Document 4). The high hydrogen carbon black uses a reaction apparatus in which a combustion gas generation zone, a reaction zone, and a reaction stop zone are connected in series, and generates high-temperature combustion gas in the combustion gas generation zone, and then the reaction zone. Obtained by spraying the raw material to form a reaction gas stream containing carbon black, and then quenching the reaction gas stream by a multistage rapid refrigerant introduction means in the reaction stop zone to terminate the reaction. Is. High hydrogen carbon black exceeds the normal hydrogen release rate.

In recent years, there has been an increasing demand for fuel efficiency reduction of automobiles in connection with the global movement of regulation of carbon dioxide emissions due to increasing interest in environmental problems. In order to meet such demands, a rubber composition in which high-hydrogen carbon black is blended with a modified rubber has been proposed, and a tire with reduced rolling resistance has been proposed (see Patent Document 5).
However, in the above Patent Documents 1 to 5, the wear resistance is not further improved by combining a modified natural rubber phospholipid with a modified diene polymer rubber.

JP-A-6-329838 JP-A-6-56902 JP-A-6-56906 WO2004 / 052935 publication WO2010 / 038768

  In consideration of the above-described conventional techniques, the present invention includes a specific natural rubber and a modified conjugated diene polymer as a rubber component, and the use of carbon black having specific physical properties does not impair the properties of the rubber component. Another object of the present invention is to provide a rubber composition and a tire using the same, which can improve wear resistance at a high level.

  The present inventor has a rubber composition containing a specific natural rubber, a specific conjugated diene polymer, and a rubber compounding carbon black having specific properties, thereby achieving the above-described rubber composition and The present inventors have found that a tire using the tire can be obtained and completed the present invention.

That is, the present invention resides in the following [1] to [10].
[1] A natural rubber obtained from a natural rubber latex obtained by hydrolyzing a phospholipid of a natural rubber molecule with an enzyme, and at least one selected from a silicon atom, a tin atom, a sulfur atom, an oxygen atom and a titanium atom, A rubber component containing a conjugated diene polymer contained in any of the polymerization initiation terminal and the polymer chain;
Using a reactor in which a combustion gas generation zone, a reaction zone, and a reaction stop zone are connected in series, high temperature combustion gas is generated in the combustion gas generation zone, and then a raw material is sprayed into the reaction zone. A carbon black for rubber compound obtained by quenching a reaction gas stream containing carbon black and terminating the reaction,
A rubber composition in which the carbon black for rubber blending satisfies the following relational expressions (1) and (2).
10 <X <40 (1)
90 <Z <100 (2)
(However, X represents the toluene coloring permeability (%) of carbon black after introduction of the first quenching medium from the raw material introduction position, and Z represents the toluene coloring permeability of carbon black after the last quenching medium introduction ( %).)
[2] The rubber composition according to [1], wherein the modified conjugated diene-based polymer is a copolymer of an aromatic vinyl compound and a conjugated diene compound.
[3] The carbon black for compounding rubber has a residence time in the zone from when the raw material is sprayed into the reaction zone until the first quenching medium is introduced to t1 (seconds). The average reaction temperature is T1 (° C.), the residence time in the zone from the introduction of the first quenching medium to the introduction of the second quenching medium is t2 (seconds), and the average reaction in this zone The temperature is T2 (° C.), and the residence time in the zone from the introduction of the second quenching medium to the introduction of the last quenching medium is t3 (seconds), and the average reaction temperature in this zone Is T3 (° C.), the carbon black for rubber compounding has the following relational expressions (3), (4) and (5):
2.00 ≦ α1 ≦ 5.00 (3)
5.00 ≦ α2 ≦ 9.00 (4)
−2.5 × (α1 + α2) + 85.0 ≦ β ≦ 90.0 (5)
(However, α1 = t1 × T1, α2 = t2 × T2, and β = t3 × T3.) The rubber composition according to the above (1), which is a high hydrogen carbon black obtained by controlling so as to satisfy .
[4] The carbon black for rubber blending has the following relational expressions (6), (7) and (8):
20 <X <40 (6)
50 <Y <60 (7)
90 <Z <95 (8)
(In the formula, Y represents the toluene coloring permeability of carbon black after introduction of the second quenching medium, and X and Z are the same as described above.)
The rubber composition according to the above [1], which is obtained by controlling to satisfy the above.
[5] The rubber composition according to [1], wherein the carbon black for rubber blending has a hydrogen release rate higher than 0.3% by mass.
[6] Dibutyl phthalate absorption (DBP) in the carbon black for rubber blending is 95 mL / 100 g or more and 220 mL / 100 g or less, compressed DBP absorption (24M4DBP) is 90 mL / 100 g or more and 200 mL / 100 g or less, and cetyl The rubber composition as described in [1] above, wherein the trimethylammonium bromide adsorption specific surface area (CTAB) is 70 m ² / g or more and 200 m ² / g or less.
[7] The rubber composition according to [1], wherein the rubber composition contains 5 parts by mass or more and 80 parts by mass or less of the treated natural rubber with respect to 100 parts by mass of the rubber component.
[8] The rubber composition according to [1], wherein the rubber composition contains 5 parts by weight or more and 80 parts by weight or less of the modified conjugated diene polymer with respect to 100 parts by weight of the rubber component.
[9] The rubber composition according to [1], wherein the rubber composition contains 10 parts by weight or more and 250 parts by weight or less of the carbon black for rubber blending with respect to 100 parts by weight of a rubber component.
[10] A tire using the rubber composition according to any one of [1] to [9].

  According to the present invention, the stable properties of the natural rubber obtained are not impaired, and the ester bond in the phospholipid of the natural rubber is hydrolyzed. The resulting hydroxyl group improves the affinity with high hydrogen carbon black, which is a carbon black for rubber compounding, and, in combination with the modified conjugated diene polymer, a rubber composition with excellent wear resistance and rolling resistance. An article and a tire using the same are provided.

It is a partial longitudinal cross-sectional front view of an example of the carbon black manufacturing furnace for manufacturing the carbon black for rubber compounding (high hydrogen carbon black) used for this invention.

Hereinafter, embodiments of the present invention will be described in detail.
The rubber composition of the present invention comprises a natural rubber obtained from a natural rubber latex obtained by hydrolyzing a phospholipid of a natural rubber molecule with an enzyme, and at least one selected from a silicon atom, a tin atom, a sulfur atom, an oxygen atom and a titanium atom. A rubber component comprising a conjugated diene polymer containing a polymerization active terminal, a polymerization initiating terminal, and a polymer chain,
Using a reactor in which a combustion gas generation zone, a reaction zone, and a reaction stop zone are connected in series, high temperature combustion gas is generated in the combustion gas generation zone, and then a raw material is sprayed into the reaction zone. A carbon black for rubber compound obtained by quenching a reaction gas stream containing carbon black and terminating the reaction,
The rubber compounding carbon black satisfies the following relational expressions (1) and (2).
10 <X <40 (1)
90 <Z <100 (2)
(However, X represents the toluene coloring permeability (%) of carbon black after introduction of the first quenching medium from the raw material introduction position, and Z represents the toluene coloring permeability of carbon black after the last quenching medium introduction ( %).)

<Natural rubber>
The natural rubber used in the present invention is obtained from a natural rubber latex obtained by hydrolyzing a natural rubber molecule phospholipid with an enzyme.
The natural rubber latex used as a raw material means a field latex obtained from a natural rubber tree, and either a commercially available ammonia-treated latex or a fresh field latex can be used as the latex.
In the present invention, the latex is preferably adjusted to pH 7 or higher within 1 hour after collection. When such a latex is used, it is easy to uniformly disperse the added enzyme in the latex solution. Examples of the added enzyme include phospholipase NS44151 (2000 LEU / g).
Usually, latexes rich in phospholipids are not preferred because of their low oxidative aging properties (PRI). However, the natural rubber latex is modified by the above treatment method and exhibits stable characteristics with high oxidative aging characteristics.
With the above treatment, a natural rubber latex having a PRI of 85 or less, preferably 80 or less, can be improved to 90 or more by enzyme treatment, but already 90 or more natural rubber latex is sufficiently improved by enzyme treatment. I can't expect it.

Examples of the enzyme that degrades phospholipids in natural rubber latex include lipase and / or phospholipase, which are triacylglycerol hydrolases used as measurement indicators as described above.
Triacylglycerol hydrolases are a diverse group of enzymes that often have one or more activities, such as lipase, phospholipase, lysophospholipase, cholesterol esterase, cutinase, amidase, galactolipase and other esterase type activities. An enzyme with Which activity is the main activity depends on the application of the enzyme and its conditions. Triglycerol hydrolase belongs to IUBMB Enzyme Nomenclature 3.1.1. EC3 represents a hydrolase. EC3.1 represents working on ester bonds. EC3.1.1 represents a carboxylic ester hydrolase. Enzymes related to the present invention are classified in EC 3.1.4 which represents phosphodiester hydrolase. Esterase (EC 3.1.1.1) is an enzyme that catalyzes the production of alcohol and carboxylate anions by hydrolyzing water-soluble carboxylic acid esters containing short-chain fatty acid triglycerides.

The lipase and phospholipase are not particularly limited, and any of those derived from bacteria, those derived from filamentous fungi, and those derived from yeast may be used.
Lipase (EC 3.1.1.3) is an enzyme that catalyzes the hydrolysis of esters with a wide range of carboxyl groups and, for example, decomposes triglycerides to release fatty acids. Some lipases have phospholipase activity and / or galactolipase activity (eg, US Pat. No. 6,103,605 and US Pat. No. 6,852,346), and may have sterol esterase activity (EC 3.1.1.13).
Phospholipase is an enzyme that catalyzes the hydrolysis of phospholipids having fatty acids at the sn1 and sn2 positions of the glycerol skeleton, and the sn3 position esterified with phosphoric acid. Phosphoric acid may in turn be esterified to an amino alcohol. There are several types of phospholipases that catalyze the hydrolysis of fatty acyl moieties. These phospholipases include phospholipase A1 (EC 3.1.1.32), phospholipase A2 (EC 3.1.1.4) and lysophospholipase (EC 3.1.1.5). Phospholipase C (EC 3.1.4.3) and phospholipase D (EC 3.1.4.4) hydrolyze phosphate groups from phospholipids, but do not degrade fatty acids like phospholipase A1, phospholipase A2 and phospholipase B. Phospholipase A1 (EC 3.1.1.32) catalyzes the deacylation of the fatty acyl group at the sn1 position to produce lysophospholipid and fatty acid from diacylglycerophospholipid. Phospholipase A2 (EC 3.1.1.4) catalyzes the deacylation of the fatty acyl group at the sn2 position, and produces lysophospholipid and fatty acid from diacylglycerophosphate. Lysophospholipase (EC 3.1.1.5) is known as phospholipase B and catalyzes the hydrolysis of fatty acid acyl groups of lysophospholipids. Phospholipase C (EC 3.1.4.3) catalyzes the hydrolysis of phosphotidylcholine to 1,2-diacylglycerol and choline phosphate. Phospholipase D (EC 3.1.4.4) catalyzes the hydrolysis of the phosphodiester bond at the end of phosphotidylcholine, producing choline and phosphotidic acid.

Phospholipases that can be used include Tuber, Venticillium, Neurospora, Helicosporum, Aspergillus or Fuzarium, especially T. Borchi, Tuba Borchi T. albidum, V. dahiliae, V. tenerum, N. crassa, Helicosporium sp. HN1, Aspergillus oryzae (A) .oryzae), or phospholipase derived from F. venenatum.
A particularly used phospholipase is the phospholipase described in U.S. Patent 7,396,807 B2, SEQ ID NO: 1 (T. borchii), SEQ ID NO: 3 (V. dahiliae). SEQ ID NO: 4 (N. crassa), SEQ ID NO: 5 (Helicosporium sp. HN1), SEQ ID NO: 7 (A. oryzae) ], SEQ ID NO: 8 (N. crassa), SEQ ID NO: 9 (T.albidum), SEQ ID NO: 10 (T.albidum) ], SEQ ID NO: 12 (V. tenerum), and SEQ ID NO: 16 (F. venenatum), the phospholipase specified in US Patent 7,396,807 B2 represented by the amino acid sequence. Contains.

Specifically, the phospholipase comprises SEQ ID NO: 1 (T. borchii) amino acid sequence 92-211, SEQ ID NO: 3 (V. dahiliae) amino acid sequence 38-145, SEQ ID NO: 4 (N. crassa) amino acid sequence 44-151, SEQ ID NO: 7 (A. oryzae) amino acid sequence 37-157, SEQ ID NO; 8 (N. crassa) amino acid sequence 58-168, SEQ ID NO: 10 (T. albidum) amino acid sequence 91-210, SEQ ID NO: 12 (Verticillium A polypeptide having an amino acid sequence selected from the group consisting of amino acid sequences 30 to 137 of V. tenerum and amino acid sequences 29 to 149 of SEQ ID NO: 16 [F. venenatum] .
The phospholipases that can be used are the amino acid sequences 91 to 210 of SEQ ID NO: 10 (T. albidum), the amino acid sequence 92 to SEQ ID NO: 1 (T. borchii). 211, SEQ ID NO: 12 amino acid sequence 30-137 of V. tenerum, SEQ ID NO: 3 amino acid sequence 38-145 of V. dahiliae, SEQ ID NO: 4 (N. crassa) amino acid sequence 44-151, SEQ ID NO: 7 (A. oryzae) amino acid sequence 37-157, SEQ ID NO: 8 (Neporus) A polyamino acid sequence selected from the group consisting of amino acid sequences 58 to 168 of P. crassa, or amino acid sequences 29 to 149 of SEQ ID NO: 16 [F. venenatum] A phospholipase that is at least 60% identical to a peptide. Depending on the purpose of the present invention, the degree of identity of the two amino acid sequences can be determined by using the Needle-Wunsch algorithm (Needleman and Wunsch, 1970, J.MOl. Biol, 48: 443-453) according to the Needle program (EMBOSS: The European Molecular Biology Open Software Suite, Ruce et al, 2000, Trends Genet. 16: 276-277), preferably using version 5.0.0 or later. The parameters used are a gap opening penalty of 10, a gap extension penalty of 0.5, and an EBLOSUM62 (EMBOSS version of BLOSUM62) substitution matrix. The output of Needle classified as “longest identity” and (obtained using the nobrif option) is used as the same percentage and is calculated as follows:
[Identical residues × IOO) / (Length of Alignment-Total Number of Gaps in A1ignmet)]

The phospholipases that can be used are the amino acid sequences 91 to 210 of SEQ ID NO: 10 (T. albidum), the amino acid sequence 92 to SEQ ID NO: 1 (T. borchii). 211, SEQ ID NO: 12 amino acid sequence 30-137 of V. tenerum, SEQ ID NO: 3 amino acid sequence 38-145 of V. dahiliae, SEQ ID NO: 4 (N. crassa) amino acid sequence 44-151, SEQ ID NO: 7 (A. oryzae) amino acid sequence 37-157, SEQ ID NO: 8 (Neporus) A polyamino acid sequence selected from the group consisting of amino acid sequences 58 to 168 of P. crassa, or amino acid sequences 29 to 149 of SEQ ID NO: 16 [F. venenatum] At least 65%, at least 70%, at least 75% with the peptide, 80% even without, at least 85%, at least 90%, at least 95%, or at least 99% identical phospholipase.
Lipases and phospholipases are added in an effective amount that degrades phospholipids in natural rubber latex by 50% or more. The specific effects of these enzymes are shown in the examples.

  Also, the lipase and phospholipase are expressed in international units of 100 (LU / g or LEU / g) or more, preferably 10,000 (LU / g or LEU / g) or more, more preferably 100,000 (LU / g or LEU / g). g) or better. Lipase activity units can be measured using lipase (LU) analysis. In this, 1 LU (lipase unit) is the amount of enzyme that evacuates 1 micromole of butyric acid that can be titrated per minute under the lipase (LU) analysis conditions of the materials and methods. Similarly, phospholipase activity units can be measured using phospholipase (LEU) analysis. Of these, 1 LEU (phospholipase unit) evacuates lecithin from titratable fatty acids released by 1 LEU standard enzyme per minute under the analytical conditions described in the phospholipase (LEU) analysis of the material and method. The amount of enzyme to be.

Examples of such lipases and phospholipases are commercially available NS44151 (manufactured by Novozymes), lipase M “Amano” 10 (commercial product manufactured by Amano Enzyme Co., Ltd.), lipase OF (commercial product manufactured by Meika Inc.), phospholipase A1 (Sankyo Co., Ltd.) Product made by a corporation | Co., Ltd.) etc. can be mentioned.
In addition, in the use of the above-mentioned indicator enzyme, it is preferable to use an enzyme having a purity of 2,000 LEU / g (Novozymes standard unit) or higher phospholipase (manufactured by Novozymes) or higher.
The amount of lipase and / or phospholipase added during such enzyme treatment is in the range of 0.01 to 10 parts by weight, particularly 0.1 to 5 parts by weight, based on 100 parts by weight of the solid component in the natural rubber latex. It is preferable. If the addition amount is in the above range, a decomposition rate of 50% or more of the phospholipid in the natural rubber latex can be achieved.

The natural rubber latex according to the present invention may be further subjected to an enzyme treatment with a protease in addition to lipase and / or phospholipase.
Like the lipase and phospholipase, the protease is not particularly limited, and may be any of bacteria, filamentous fungi, or yeast. The titer of the protease is preferably 50 (KNPU / g) or more, 100 (KNPU / g) or more, preferably 1,000 (KNPU / g) or more, more preferably 10,000 (KNPU / g). g) or more, and more preferably 100,000 (IDJPU / g) or more. Units of protease activity can be measured as kilo-Novo-protease units (KNPU / g) per gram sample under the analytical conditions described in the Protease (KNPU) analysis in the Materials and Methods section. Examples of such proteases include commercially available Alcalase 2.5L-type DX (manufactured by Novozymes), pro leather FG-F (manufactured by Amano Enzymes) and the like.
In the present invention, in addition to the above-described enzymes (in addition to protease), peptidase, cellulase, pectinase, esterase, amylase and the like can be used in combination.

In addition, when such an enzyme is added, other additives such as phosphates such as potassium phosphate, potassium phosphate and sodium phosphate, and acetates such as potassium acetate and sodium acetate as pH adjusters. Furthermore, acids such as sulfuric acid, acetic acid, hydrochloric acid, nitric acid, citric acid and succinic acid or salts thereof, or ammonia, sodium hydroxide, potassium hydroxide, sodium carbonate, sodium hydrogen carbonate and the like can be used.
In the present invention, the enzyme treatment is preferably performed at an optimum pH, but considering the dispersibility in latex, pH 5 to 11 is preferable, and pH 7 to 10 is particularly preferable.

In the present invention, the enzyme treatment is performed at room temperature (25 ° C.) to 70 ° C. or less, preferably at a temperature of 60 ° C. or less, and more preferably at 50 ° C. or less.
When the enzyme treatment temperature exceeds 70 ° C., the stability of the natural rubber latex decreases, and the latex coagulates during the enzyme treatment. After coagulation, the degradation effect by the enzyme decreases. For this reason, it becomes difficult to produce natural rubber having excellent processability.

  In the present invention, the enzyme treatment time is 12 hours or longer, more preferably 16 hours or longer and 48 hours or shorter. With such a reaction time, the phospholipid in the latex is sufficiently decomposed. Phospholipid degradation is 50% or more, preferably at least 60%, at least 70%, at least 80%, at least 90%. The amount of undegraded phospholipid in the decomposed natural rubber latex is 0.65% or less, preferably 0.50% by weight or less, more preferably 0.30% by weight or less, and further 0.20% by weight or less. , Preferably 0.10 wt% or less. For this reason, if it is the said preferable processing time, reaction can fully be achieved and sufficient decomposition | disassembly of a phospholipid and undegraded phospholipid amount can be decreased as much as possible.

The natural rubber latex according to the present invention is preferably treated by using a surfactant in combination with the enzyme treatment. As the surfactant, nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants and the like can be used. In particular, nonionic surfactants and anionic surfactants can be used. It is preferable to use an agent or the like.
As the nonionic surfactant, for example, polyoxyalkylene ether, polyoxyalkylene ester, polyhydric alcohol fatty acid ester, sugar fatty acid ester, and alkyl polyglycoside are suitable.
As the anionic surfactant, for example, carboxylic acid type, sulfonic acid type, sulfuric acid ester type, and phosphoric acid ester type are suitable.
Examples of the carboxylic acid surfactant include fatty acid salts, polyvalent carboxylates, rosinates, dimer salts, polymer acid salts, tall oil fatty acid salts, and the like. Examples of the sulfonic acid surfactant include alkylbenzene sulfonate, alkyl sulfonate, alkyl naphthalene sulfonate, naphthalene sulfonate, and diphenyl ether sulfonate. Examples of the sulfate ester surfactants include alkyl sulfate ester salts, polyoxyalkylene alkyl sulfate esters, polyoxyalkylene alkyl phenyl ether sulfates, tristyrenated phenol sulfate esters, polyoxyalkylene distyrenated phenol sulfate esters. Examples include salts. Examples of phosphate ester surfactants include alkyl phosphate ester salts and polyoxyalkylene phosphate ester salts.

  The natural rubber latex treated with the enzyme as described above coagulates without completely separating non-rubber components. When the non-rubber component is separated, the aging resistance is poor. The rubber component obtained by coagulating the treated latex is washed and then dried using a normal dryer such as a vacuum dryer, air dryer, drum dryer or the like, whereby the natural rubber used in the present invention can be obtained. .

<Modified conjugated diene polymer>
In the rubber composition of the present invention, at least one selected from a silicon atom, a tin atom, a sulfur atom, an oxygen atom and a titanium atom is used as a rubber component to be used in any one of a polymerization active terminal, a polymerization start terminal and a polymerization chain. Containing conjugated diene polymers are included.

  The conjugated diene polymer that can be used can be produced as a polymer having an organometallic active site in the molecule, and the production method is not particularly limited, and is a solution polymerization method, a gas phase polymerization method, Any of the bulk polymerization methods can be used, but the solution polymerization method is particularly preferable. Moreover, any of a batch type and a continuous type may be sufficient as the superposition | polymerization form.

The metal of the active site is preferably one selected from alkali metals and alkaline earth metals, and lithium metal is particularly preferable.
In the solution polymerization method, for example, a target polymer can be produced by anionic polymerization of a conjugated diene compound alone or a conjugated diene compound and an aromatic vinyl compound using a lithium compound as a polymerization initiator. As the conjugated diene polymer in the present embodiment, a conjugated diene polymer obtained by copolymerizing a (co) polymer of a conjugated diene compound or a conjugated diene compound and an aromatic vinyl compound from the viewpoint that the glass transition temperature can be controlled. Polymers are preferred. The (co) polymer means a polymer or a copolymer.

Furthermore, it is also effective to mix a halogen-containing monomer and activate the halogen atom in the polymer with an organometallic compound. For example, it is also effective to lithiate the bromine moiety of a copolymer containing an isobutylene unit, a paramethylstyrene unit and a parabromomethylstyrene unit to form an active site.
The active site may be present in the polymer molecule, and may be present in any of the polymerization active terminal, the polymerization initiation terminal and the polymerization chain. When the polymer is obtained by anionic polymerization using an alkali metal compound and / or an alkaline earth metal compound as a polymerization initiator, generally, the active site is located at the end of the polymer.
For example, if the active terminal is reacted with a compound containing at least one selected from a silicon atom, a tin atom, a sulfur atom, an oxygen atom and a titanium atom, the conjugated diene polymer used for the rubber component of the present invention Is obtained.

Examples of the conjugated diene compound include 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethylbutadiene, 2-phenyl-1,3-butadiene, 1,3-hexadiene, and the like. These may be used alone or in combination of two or more, and among these, 1,3-butadiene and isoprene are particularly preferable.
Examples of the aromatic vinyl compound used for copolymerization with these conjugated diene compounds include styrene, α-methylstyrene, 1-vinylnaphthalene, 3-vinyltoluene, ethylvinylbenzene, divinylbenzene, and 4-cyclohexylstyrene. 2,4,6-trimethylstyrene and the like. These may be used singly or in combination of two or more, but among these, styrene is particularly preferable.
Furthermore, when copolymerization is performed using a conjugated diene compound and an aromatic vinyl compound as monomers, the use of 1,3-butadiene and styrene, respectively, in terms of practicality such as the availability of monomers, And anionic polymerization characteristics are particularly preferred in view of the living property.
When the solution polymerization method is used, the monomer concentration in the solvent is preferably in the range of 5 to 50% by mass, more preferably in the range of 10 to 30% by mass. When copolymerization is performed using a conjugated diene compound and an aromatic vinyl compound, the content of the aromatic vinyl compound in the charged monomer mixture is preferably in the range of 1 to 60% by mass, and more preferably in the range of 5 to 45%. % Range is preferred.

  The lithium compound of the polymerization initiator is not particularly limited, but hydrocarbyl lithium and lithium amide compounds are preferably used. When the former hydrocarbyl lithium is used, it has a hydrocarbyl group at the polymerization initiation terminal and the other terminal. A conjugated diene polymer having a polymerization active site is obtained. When the latter lithium amide compound is used, a conjugated diene polymer having a nitrogen-containing group at the polymerization initiation terminal and the other terminal being a polymerization active site is obtained.

  As the hydrocarbyl lithium, those having a hydrocarbyl group having 2 to 20 carbon atoms are preferable, for example, ethyl lithium, n-propyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-octyl lithium, n-decyl. Examples include lithium, phenyl lithium, 2-naphthyl lithium, 2-butyl-phenyl lithium, 4-phenyl-butyl lithium, cyclohexyl lithium, cyclopentyl lithium, reaction products of diisopropenylbenzene and butyl lithium, and the like. Of these, n-butyllithium is preferred.

  On the other hand, as the lithium amide compound, for example, lithium hexamethylene imide, lithium pyrrolidide, lithium piperidide, lithium heptamethylene imide, lithium dodecamethylene imide, lithium dimethylamide, lithium diethylamide, lithium dibutylamide, lithium dipropylamide, lithium Diheptylamide, lithium dihexylamide, lithium dioctylamide, lithium di-2-ethylhexylamide, lithium didecylamide, lithium-N-methylpiperazide, lithium ethylpropylamide, lithium ethylbutyramide, lithium methylbutyramide, lithium ethylbenzylamide, Examples include lithium methyl phenethyl amide.

Among these, cyclic lithium amides such as lithium hexamethylene imide, lithium pyrrolidide, lithium piperidide, lithium heptamethylene imide, and lithium dodecamethylene imide are preferable from the viewpoint of the interaction effect on carbon black and the ability to initiate polymerization. Particularly preferred are lithium hexamethylene imide and lithium pyrrolidide.
These lithium amide compounds are generally prepared in advance from a secondary amine and a lithium compound for polymerization, but can also be prepared in a polymerization system (in-situ). The amount of the polymerization initiator used is preferably selected in the range of 0.2 to 20 mmol per 100 g of monomer.

There is no restriction | limiting in particular as a method of manufacturing a conjugated diene polymer by anionic polymerization using the said lithium compound as a polymerization initiator, A conventionally well-known method can be used.
Specifically, in an organic solvent inert to the reaction, for example, in a hydrocarbon solvent such as an aliphatic, alicyclic or aromatic hydrocarbon compound, a conjugated diene compound or a conjugated diene compound and an aromatic vinyl compound are used. The desired conjugated diene polymer can be obtained by subjecting the lithium compound as a polymerization initiator to anionic polymerization in the presence of a randomizer to be used, if desired.

  The hydrocarbon solvent is preferably one having 3 to 8 carbon atoms, for example, propane, n-butane, isobutane, n-pentane, isopentane, n-hexane, cyclohexane, propene, 1-butene, isobutene, trans- Examples include 2-butene, cis-2-butene, 1-pentene, 2-pentene, 1-hexene, 2-hexene, benzene, toluene, xylene, and ethylbenzene. These may be used alone or in combination of two or more.

The randomizer used as desired is a control of the microstructure of the conjugated diene polymer, such as an increase in 1,2 bonds in the butadiene portion in the butadiene-styrene copolymer, an increase in 3,4 bonds in the isoprene polymer, or the like. It is a compound having an effect of controlling the composition distribution of monomer units in a conjugated diene compound-aromatic vinyl compound copolymer, for example, randomizing butadiene units and styrene units in a butadiene-styrene copolymer. The randomizer is not particularly limited, and any one of known compounds generally used as a conventional randomizer can be appropriately selected and used.
Specifically, dimethoxybenzene, tetrahydrofuran, dimethoxyethane, diethylene glycol dibutyl ether, diethylene glycol dimethyl ether, bistetrahydrofurylpropane, triethylamine, pyridine, N-methylmorpholine, N, N, N ′, N′-tetramethylethylenediamine, 1, Examples include ethers such as 2-dipiperidinoethane and tertiary amines. Further, potassium salts such as potassium-t-amylate and potassium-t-butoxide, and sodium salts such as sodium-t-amylate can also be used.
One of these randomizers may be used alone, or two or more thereof may be used in combination. The amount used is preferably selected in the range of 0.01 to 1000 molar equivalents per mole of the lithium compound.

The temperature in this polymerization reaction is preferably selected in the range of 0 to 150 ° C, more preferably in the range of 20 to 130 ° C. The polymerization reaction can be carried out under generated pressure, but it is usually desirable to operate at a pressure sufficient to keep the monomer in a substantially liquid phase. That is, the pressure depends on the particular material being polymerized, the polymerization medium used and the polymerization temperature, but higher pressures can be used if desired, such pressure being a gas that is inert with respect to the polymerization reaction. Can be obtained by an appropriate method such as pressurizing.
In this polymerization, it is desirable that all raw materials involved in the polymerization, such as a polymerization initiator, a solvent, and a monomer, are obtained by removing reaction inhibitors such as water, oxygen, carbon dioxide, and protic compounds.
In addition, when obtaining a polymer as an elastomer, it is preferable that the glass transition point (Tg) calculated | required by the differential thermal analysis method of the obtained polymer or copolymer is the range of -110 degreeC--15 degreeC. It is difficult to obtain a polymer having a glass transition point of less than −110 ° C., and when it exceeds −15 ° C., the viscosity becomes too high in the room temperature region, which may make handling difficult.

On the other hand, when the modified conjugated diene polymer is produced by coordination polymerization using a rare earth metal compound as a polymerization initiator, the following (A) component, (B) component, and (C) component may be used in combination: preferable.
The component (a) used for the coordination polymerization is selected from a rare earth metal compound, a complex compound of a rare earth metal compound and a Lewis base, and the like. Here, examples of rare earth metal compounds include rare earth element carboxylates, alkoxides, β-diketone complexes, phosphates and phosphites, and Lewis bases include acetylacetone, tetrahydrofuran, pyridine, N, N. -Dimethylformamide, thiophene, diphenyl ether, triethylamine, an organic phosphorus compound, monovalent or divalent alcohol, etc. are mentioned. As the rare earth element of the rare earth metal compound, lanthanum, neodymium, praseodymium, samarium and gadolinium are preferable, and among these, neodymium is particularly preferable. Specific examples of the component (a) include neodymium tri-2-ethylhexanoate, a complex compound thereof with acetylacetone, neodymium trineodecanoate, a complex compound thereof with acetylacetone, neodymium tri-n-butoxide, and the like. It is done. These components (a) may be used alone or in combination of two or more.

The component (b) used in the coordination polymerization is selected from organoaluminum compounds. As the organoaluminum compound, specifically, a trihydrocarbyl aluminum compound represented by the formula: R ¹² ₃ Al, a hydrocarbyl aluminum hydride represented by the formula: R ¹² ₂ AlH or R ¹² AlH ₂ (wherein R ¹² are each independently a hydrocarbon group having 1 to 30 carbon atoms, and hydrocarbylaluminoxane compounds having a hydrocarbon group having 1 to 30 carbon atoms.
Specific examples of the organoaluminum compound include trialkylaluminum, dialkylaluminum hydride, alkylaluminum dihydride, and alkylaluminoxane. These compounds may be used alone or in combination of two or more. In addition, as (b) component, it is preferable to use aluminoxane and another organoaluminum compound in combination.

  The component (c) used in the coordination polymerization is a compound having a hydrolyzable halogen or a complex compound thereof with a Lewis base; an organic halide having a tertiary alkyl halide, benzyl halide or allyl halide; a non-coordinating anion And an ionic compound comprising a counter cation. Specific examples of the component (c) include alkylaluminum dichloride, dialkylaluminum chloride, silicon tetrachloride, tin tetrachloride, zinc chloride and Lewis base complexes such as alcohol, magnesium chloride and alcohol such as Lewis. Examples include complexes with bases, benzyl chloride, t-butyl chloride, benzyl bromide, t-butyl bromide, triphenylcarbonium tetrakis (pentafluorophenyl) borate and the like. These components (c) may be used alone or in combination of two or more.

  The polymerization initiator is preliminarily used by using the same conjugated diene compound and / or non-conjugated diene compound as the polymerization monomer, if necessary, in addition to the components (a), (b) and (c). May be prepared. Further, part or all of the component (a) or the component (c) may be supported on an inert solid. Although the usage-amount of said each component can be set suitably, (a) component is 0.001-0.5 millimoles (mmol) per 100g of monomers normally. In addition, (b) component / (b) component is preferably 5 to 1,000, and (c) component / (b) component is preferably 0.5 to 10 in molar ratio.

The polymerization temperature in the coordination polymerization is preferably in the range of −80 to 150 ° C., and more preferably in the range of −20 to 120 ° C. Moreover, as a solvent used for coordination polymerization, a hydrocarbon solvent inert to the reaction exemplified in the above-mentioned anionic polymerization can be used, and the concentration of the monomer in the reaction solution is the same as in the case of anionic polymerization. . Furthermore, the reaction pressure in coordination polymerization is the same as that in the case of anionic polymerization, and it is desirable that the raw material used for the reaction substantially removes reaction inhibitors such as water, oxygen, carbon dioxide, and protic compounds.
The modified conjugated diene polymer is preferably an anion-polymerized organic alkali metal compound, particularly alkyllithium.

In the conjugated diene polymer used in the present invention, as an unmodified and / or modified low molecular weight diene copolymer, the content of the aromatic vinyl compound unit is 1% by mass or more and 60% in the property before modification or before modification. It is preferable that the vinyl bond content of the conjugated diene moiety is 5% by mass or more and 80% by mass or less. If the content of the aromatic vinyl compound unit and the vinyl bond content of the conjugated diene compound portion are not within the above ranges, sufficient compatibility between ensuring the workability of the rubber composition and reducing the loss tangent (tan δ) of the rubber composition is achieved. It may not be possible.
The content of the aromatic vinyl compound unit is more preferably 10% by mass to 50% by mass, and the vinyl bond content of the conjugated diene moiety is preferably 10% by mass to 70% by mass.

The conjugated diene polymer used in the present invention is a modification obtained by subjecting a polymerization active end to a compound containing at least one selected from a silicon atom, a tin atom, a sulfur atom, an oxygen atom and a titanium atom after the polymerization reaction. A conjugated diene polymer is preferred.
Here, the conjugated diene polymer having a polymerizable active terminal is conjugated with an aromatic vinyl compound using an organic alkali metal compound, preferably a lithium compound, as described in the production of the conjugated diene polymer. The diene compound can be obtained by anionic polymerization in the same manner as described above. In this case, the reaction conditions are appropriately selected so that the resulting low molecular weight diene copolymer having an active terminal has the above-described properties.
Nitrogen-containing compounds, silicon-containing compounds, tin-containing compounds, and the like can be used as modifiers that are reacted with the active ends of the low molecular weight diene copolymer thus obtained. Nitrogen-containing compounds that can be used as the modifier include bis (diethylamino) benzophenone, dimethylimidazolidinone, N-methylpyrrolidone, 4-dimethylaminobenzylideneaniline, and the like. By using these nitrogen-containing compounds as modifiers, functional groups containing nitrogen such as substituted and unsubstituted amino groups, amide groups, imino groups, imidazole residues, nitrile groups, and pyridyl groups can be introduced.
In the modification reaction in this embodiment, the low molecular weight diene copolymer having an active terminal to be used is preferably such that at least 10% of the polymer chains have a living property.

  The first polymer in the present embodiment is the following general formula (I) with respect to the conjugated diene polymer having an organometallic active site in the molecule thus obtained:

〔上記式（Ｉ）中、ａ＋ｂ＋ｃ＝４（但し、ｂは１〜３の整数、ａは０〜２の整数、ｃは１〜３の整数である）であり、Ａは飽和環状３級アミン化合物残基、不飽和環状３級アミン化合物残基、イミン残基、ニトリル基、（チオ）イソシアナート基、（チオ）エポキシ基、イソシアヌル酸トリヒドロカルビルエステル残基、炭酸ジヒドロカルビルエステル残基、ニトリル基、ピリジン基、（チオ）ケトン基、（チオ）アルデヒド基、アミド基、（チオ）カルボン酸エステル残基、（チオ）カルボン酸エステル残基の金属塩、カルボン酸無水物残基、カルボン酸ハロゲン化合物残基、並びに加水分解可能な基を有する２級アミノ基またはメルカプト基の中から選ばれる少なくとも１種の官能基であり、Ａが複数のときは同一であっても異なっていてもよい。
Ｒ¹は、炭素数１〜２０の一価の脂肪族炭化水素基、炭素数６〜１８の一価の芳香族炭化水素基またはハロゲン原子であり、Ｒ¹が複数のときは同一であっても異なっていてもよい。Ｒ²は、炭素数１〜２０の一価の脂肪族炭化水素基又は炭素数６〜１８の一価の芳香族炭化水素基であり、Ｒ²が複数のときは同一であっても異なっていてもよい。Ｒ³は、炭素数１〜２０の二価の炭化水素基又は炭素数６〜１８の二価の芳香族炭化水素基であり、Ｒ³が複数のときは同一であっても異なっていてもよい。〕で表される変性剤、及びその縮合物を反応させて得られる。

[In the above formula (I), a + b + c = 4 (where b is an integer of 1 to 3, a is an integer of 0 to 2 and c is an integer of 1 to 3), and A is a saturated cyclic tertiary amine Compound residue, unsaturated cyclic tertiary amine compound residue, imine residue, nitrile group, (thio) isocyanate group, (thio) epoxy group, isocyanuric acid trihydrocarbyl ester residue, carbonic acid dihydrocarbyl ester residue, nitrile Group, pyridine group, (thio) ketone group, (thio) aldehyde group, amide group, (thio) carboxylic acid ester residue, metal salt of (thio) carboxylic acid ester residue, carboxylic anhydride residue, carboxylic acid Halogen compound residue, and at least one functional group selected from a secondary amino group or mercapto group having a hydrolyzable group, and when A is plural, they may be the same or different It may be.
R ¹ is a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms, a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms or a halogen atom, and is the same when R ¹ is plural. May be different. R ² is a monovalent aliphatic hydrocarbon group having 1 to 20 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 18 carbon atoms, and when R ² is plural, they are the same or different. May be. R ³ is a divalent hydrocarbon group having 1 to 20 carbon atoms or a divalent aromatic hydrocarbon group having 6 to 18 carbon atoms, and when R ³ is plural, they may be the same or different. Good. It can be obtained by reacting a modifier represented by

In the general formula (I), R ¹ and R ² are each an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 18 carbon atoms, an aryl group having 6 to 18 carbon atoms, or an aralkyl group having 7 to 18 carbon atoms. Etc. Here, the alkyl group and alkenyl group may be linear, branched, or cyclic, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group. , Sec-butyl, tert-butyl, pentyl, hexyl, octyl, decyl, dodecyl, cyclopentyl, cyclohexyl, vinyl, propenyl, allyl, hexenyl, octenyl, cyclo A pentenyl group, a cyclohexenyl group, etc. are mentioned. The aryl group may have a substituent such as a lower alkyl group on the aromatic ring, and examples thereof include a phenyl group, a tolyl group, a xylyl group, and a naphthyl group. Furthermore, the aralkyl group may have a substituent such as a lower alkyl group on the aromatic ring, and examples thereof include a benzyl group, a phenethyl group, and a naphthylmethyl group.

The divalent inert hydrocarbon group having 1 to 20 carbon atoms in R ³ is preferably an alkylene group having 1 to 20 carbon atoms. The alkylene group may be linear, branched or cyclic, but a linear one is particularly preferable. Examples of the linear alkylene group include a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, a pentamethylene group, a hexamethylene group, an octamethylene group, a decamethylene group, and a dodecamethylene group.

Examples of the saturated cyclic tertiary amine compound residue in A include a hexamethyleneimino group, a pyrrolidinyl group, a piperidinyl group, a heptamethyleneimino group, a dodecamethyleneimino group, and the like, and an unsaturated cyclic tertiary amine Examples of the compound residue include an imidazole residue, a dihydroimidazole residue, an oxazole residue, and a pyridyl group.
The A includes a ketimine residue, a saturated cyclic tertiary amine compound residue, an imidazole residue, a dihydroimidazole residue, a pyridine group, a nitrile group, an isocyanate group, and a detachable functional group from the viewpoint of performance. It is preferably a monovalent group having at least one nitrogen-containing functional group selected from secondary amino groups, saturated cyclic tertiary amine compound residue, ketimine residue, imidazole residue, dihydroimidazole residue and It is more preferably a monovalent group having at least one selected from secondary amino groups having a detachable functional group.

  In the above general formula (I), among the functional groups in A, the imine residue includes ketimine, aldimine, and amidine residues, and the (thio) carboxylic acid hydrocarbyl ester is an unsaturated carboxylic acid such as acrylate or methacrylate. Includes ester residues. Examples of the metal of the metal salt residue of (thio) carboxylic acid include alkali metals, alkaline earth metals, aluminum, tin, and zinc.

Among the functional groups in the monovalent group represented by A, examples of the secondary amino group having a hydrolyzable group include N- (trimethylsilyl) amino group. The (thio) isocyanate group is a —NCO group or a —NCS group.
Examples of the monovalent group containing a (thio) epoxy group include a glycidoxy group, a 3,4-epoxycyclohexyl group, and those obtained by replacing the epoxy ring in these groups with a thioepoxy ring.

The modifier used in the present invention is a bifunctional hydrocarbyloxysilane compound and / or a partial condensate thereof as described above. Here, the partial condensate means a product in which a part (not all) of the SiOR groups of the hydrocarbyloxysilane compound are bonded by SiOSi by condensation.
Further, when the modifier used in the present embodiment is a monofunctional hydrocarbyloxysilane compound having one hydrocarbyloxy group directly bonded to a silicon atom, the hydrocarbyloxy group is consumed by the modification reaction, and inorganic filler such as silica is filled. Since the modifying group that interacts with the material is not introduced, the object of the present invention cannot be achieved. On the other hand, in the case of a trifunctional hydrocarbyloxysilane compound having three hydrocarbyloxy groups directly bonded to a silicon atom, a conjugated diene polymer having a plurality of active ends reacts with one molecule of the modifier, whereby Highly efficient introduction of modified ends per molecule cannot be achieved.
In the modification reaction in the present embodiment, it is preferable that the conjugated diene polymer having an active terminal to be used has at least 10% of polymer chains having a living property.

Examples of the hydrocarbyloxysilane compound represented by formula (I) include (thio) epoxy group-containing hydrocarbyloxysilane compounds such as 2-glycidoxyethyltrimethoxysilane, 2-glycidoxyethyltriethoxysilane, (2-glycidoxyethyl) methyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, (3-glycidoxypropyl) methyldimethoxysilane, 2- (3,4 -Epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyl (methyl) dimethoxysilane, and thioepoxy groups in these compounds Replace with There may be mentioned a was, among these, 3-glycidoxypropyltrimethoxysilane and 3-glycidoxypropyl triethoxysilane are particularly preferred.

  Further, as the imine residue-containing hydrocarbyloxysilane compound, N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine, N- (1-methylethylidene) -3- (tri Ethoxysilyl) -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-propanamine and their tris Trimethoxysilyl compounds, methyldiethoxysilyl compounds, ethyldiethoxysilyl compounds corresponding to ethoxysilyl compounds Examples thereof include a methyldimethoxysilyl compound and an ethyldimethoxysilyl compound. Among these, N- (1-methylpropylidene) -3- (triethoxysilyl) -1-propanamine and N- (1,3 -Dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine is particularly preferred.

  Examples of the imine (amidine) residue-containing compound include 1- [3- (triethoxysilyl) propyl] -4,5-dihydroimidazole, 1- [3- (trimethoxysilyl) propyl] -4,5- Dihydroimidazole, N- (3-triethoxysilylpropyl) -4,5-dihydroimidazole, N- (3-isopropoxysilylpropyl) -4,5-dihydroimidazole, N- (3-methyldiethoxysilylpropyl) Examples include -4,5-dihydroimidazole, and among these, N- (3-triethoxysilylpropyl) -4,5-dihydroimidazole is preferable.

  As the bifunctional hydrocarbyloxysilane compound represented by the general formula (I), for example, when A has an imidazole residue or a dihydroimidazole residue, as a specific example, 1- [3- [diethoxy (methyl) silyl] Propyl] -imidazole, 1- [3- [diethoxy (ethyl) silyl] propyl] -imidazole, 1- [3- [dipropoxy (methyl) silyl] propyl] -imidazole, 1- [3- [dipropoxy (ethyl) silyl] ] Propyl] -imidazole, 1- [3- [diethoxy (methyl) silyl] propyl] -4,5-dihydroimidazole, 1- [3- [diethoxy (ethyl) silyl] propyl] -4,5-dihydroimidazole, 1- [3- [Dipropoxy (methyl) silyl] propyl] -4,5-dihydroimidazo And 1- [3- [dipropoxy (ethyl) silyl] propyl] -4,5-dihydroimidazole, among which 1- [3- [diethoxy (methyl) silyl] propyl]- Imidazole, 1- [3- [dipropoxy (methyl) silyl] propyl] -imidazole, 1- [3- [diethoxy (methyl) silyl] propyl] -4,5-dihydroimidazole and 1- [3- [dipropoxy (methyl) ) Silyl] propyl] -4,5-dihydroimidazole is preferred.

  As the bifunctional hydrocarbyloxysilane compound represented by the general formula (I), for example, when A has a pyridyl group or a nitrile group, as a specific example, 2- [2- [diethoxy (methyl) silyl] ethyl] -Pyridine, 2- [2- [dipropoxy (methyl) silyl] ethyl] -pyridine, 2- [3- [diethoxy (methyl) silyl] propyl] -pyridine, 2- [3- [diethoxy (ethyl) silyl] propyl ] -Pyridine, 2- [3- [dipropoxy (methyl) silyl] propyl] -pyridine, 2- [3- [dipropoxy (ethyl) silyl] propyl] -pyridine, 4- [2- [diethoxy (methyl) silyl] Ethyl] -pyridine, 4- [2- [dipropoxy (methyl) silyl] ethyl] -pyridine, 4- [3- [diethoxy (methyl) Ryl] propyl] -pyridine, 4- [3- [diethoxy (ethyl) silyl] propyl] -pyridine, 4- [3- [dipropoxy (methyl) silyl] propyl] -pyridine, 4- [3- [dipropoxy (ethyl) ) Pyridine compounds such as silyl] propyl] -pyridine, 1-cyano-3- [diethoxy (methyl) silyl] -propane, 1-cyano-3- [diethoxy (ethyl) silyl] -propane, 1-cyano-3- And cyano compounds such as [dipropoxy (methyl) silyl] -propane and 1-cyano-3- [dipropoxy (ethyl) silyl] -propane. Among these, 2- [3- [diethoxy (methyl) silyl] propyl] -pyridine, 2- [3- [dipropoxy (methyl) silyl] propyl] -pyridine, 4- [3- [diethoxy (methyl) silyl ] Propyl] -pyridine, 4- [3- [dipropoxy (methyl) silyl] propyl] -pyridine, 1-cyano-3- [diethoxy (methyl) silyl] -propane and 1-cyano-3- [dipropoxy (methyl) Silyl] -propane is preferred.

As the bifunctional hydrocarbyloxysilane compound represented by the general formula (I), for example, when A has a (thio) isocyanate group or an oxazole residue, as a specific example, 1-isocyanato-3- [diethoxy (methyl) Silyl] -propane, 1-isocyanato-3- [diethoxy (ethyl) silyl] -propane, 1-isocyanato-3- [dipropoxy (methyl) silyl] -propane, 1-isocyanato-3- [dipropoxy (ethyl) silyl] -Isocyanate compounds such as propane, thioisocyanate compounds in which the isocyanate in the above isocyanate compounds is replaced by thioisocyanate, 4- [3- [diethoxy (methyl) silyl] propyl] -oxazole, 4- [3- [diethoxy (ethyl) ) Silyl] propyl] -oxazo Le 4- [3- [dipropoxy (methyl) silyl] propyl] - oxazole, 4- [3- [dipropoxy (ethyl) silyl] propyl] - such as oxazole compounds such as oxazole and the like. Among these, 1-isocyanato-3- [diethoxy (methyl) silyl] -propane, 1-isocyanato-3- [dipropoxy (methyl) silyl] -propane, 4- [3- [diethoxy (methyl) silyl] propyl ] -Oxazole and 4- [3- [dipropoxy (methyl) silyl] propyl] -oxazole are preferred.
In the present embodiment, the oxazole residue also includes an isoxazole residue.

  Furthermore, the following can be mentioned as another hydrocarbyl oxysilane compound. That is, examples of the carboxylic acid hydrocarbyl ester residue-containing compound include 3-methacryloyloxypropyltriethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-methacryloyloxypropylmethyldiethoxysilane, and 3-methacryloyloxypropyl. Examples include triisopropoxysilane, among which 3-methacryloyloxypropyltrimethoxysilane is preferable.

  Examples of the isocyanate group-containing compound include 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropylmethyldiethoxysilane, and 3-isocyanatopropyltriisopropoxysilane. Among these, 3-isocyanatopropyltriethoxysilane is preferable.

  Further, as carboxylic acid anhydride residues, 3-triethoxysilylpropyl succinic anhydride residue, 3-trimethoxysilylpropyl succinic anhydride residue, 3-methyldiethoxysilylpropyl succinic anhydride residue Among them, 3-triethoxysilylpropyl succinic anhydride residue is preferable among these.

  In the present invention, the hydrocarbyloxysilane compound having the above characteristic structure is preferably added in a stoichiometric amount or in excess of the active site, more preferably 0.3 molar equivalent or more of the apparent active site. (Normally, one mole of the modifying hydrocarbyloxysilane compound corresponds to several mole equivalents of the active site), the hydrocarbyloxysilane compound is reacted with the active site, and the active site is substantially hydrocarbyloxysilane compound. After introducing the residue, a method of adding a condensation accelerator is used.

Examples of such a condensation accelerator include a compound containing a tertiary amino group, or among group 3, 4, 5, 12, 13, 14, and 15 of the periodic table (long period type). An organic compound containing one or more elements belonging to any of the above can be used. Further, as a condensation accelerator, an alkoxide, a carboxyl containing at least one metal selected from the group consisting of titanium (Ti), zirconium (Zr), bismuth (Bi), aluminum (Al), and tin (Sn). It is preferably an acid salt or an acetylacetonate complex salt.
The condensation accelerator used here can be added before the modification reaction, but is preferably added to the modification reaction system during and / or after the modification reaction. When added before the denaturation reaction, a direct reaction with the active end occurs, and for example, a hydrocarboxy group having a protected primary amino group at the active end may not be introduced.
It is preferable to add the condensation accelerator to the reaction system immediately after the modification in which the hydrocarbylsilane compound residue is introduced. However, the polymer modified by the reaction is dried and then blended, preferably blended. In the first stage, a condensation accelerator may be added.
In this modification reaction, the conjugated diene polymer used preferably has at least 20% of polymer chains having the active site.

The second modified conjugated diene polymer in the present embodiment has the following general formula (II) at the active site of the conjugated diene polymer having an organometallic active site in the molecule.
R _a MX _b ……… (II)
[In the formula (II), each R is independently an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, and an aralkyl having 7 to 20 carbon atoms. Selected from the group, M is tin or silicon, and X is independently chlorine, bromine or iodine. A is an integer of 0 to 3, b is an integer of 1 to 4, and a + b = 4], and the general formula (III)
R ¹ _a M (OR ² ) _b ............ (III)
[In the above formula (III), R ¹ and R ² are each independently an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, and 7 carbon atoms. Selected from ˜20 aralkyl groups, M is tin or silicon, and X is independently chlorine, bromine or iodine. A is an integer of 0 to 3, b is an integer of 1 to 4, and a + b = 4], and at least one modifier selected from alkoxysilane compounds represented by Obtained by reaction.

The method for producing the polymer having the organometallic active site in the molecule is the same as in the case of the first polymer.
The modified conjugated diene polymer modified with at least one of the coupling agents represented by the general formulas (II) and (III) has at least one tin-carbon bond or silicon-carbon bond. In the general formulas (II) and (III), R or R ¹ and R ² are each independently an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, or an aryl having 6 to 20 carbon atoms. Group or an aralkyl group having 7 to 20 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, an n-butyl group, a neophyll group, a cyclohexyl group, an n-octyl group, and a 2-ethylhexyl group. . Z is tin or silicon, and X is independently chlorine or bromine. In general formula (II) and (III), a is an integer of 0-3, b is an integer of 1-4, However, it is a + b = 4.
As the coupling agent represented by the general formula (II), tin tetrachloride, RSnCl ₃ , R ₂ SnCl ₂ , R ₃ SnCl and the like are preferable, and tin tetrachloride is particularly preferable. Moreover, as a coupling agent represented by general formula (III), tetraalkoxysilane, trialkoxysilane, and dialkoxysilane are preferable, and tetraethoxysilane is particularly preferable.

The third modified diene polymer in the present embodiment is obtained by reacting a condensate of an alkoxysilane compound represented by the general formula (II) and a modifying agent represented by the general formula (III). It is a modified conjugated diene polymer.
The alkoxysilane compound represented by the general formula (II) and the modifier represented by the general formula (III) are as described above.

The method for producing the polymer having the organometallic active site in the molecule is the same as in the case of the first polymer.
Further, the kind of the condensation accelerator and the condensation reaction conditions are also as described in the production of the first polymer.

  The modified conjugated diene polymer in the present invention modified with the above-described modifier preferably contains a nitrogen atom. In general, in a rubber composition in which carbon black is blended with a rubber component containing a modified conjugated diene polymer having a nitrogen-containing functional group, the dispersibility of carbon black with respect to the rubber component is improved, and consequently hysteresis of the rubber component Since the loss is reduced, wear resistance and rolling resistance can be improved. Therefore, the use of a modified conjugated diene-based polymer having a nitrogen-containing functional group together with carbon black having a small amount of tar components present on the surface in the present invention greatly improves the dispersibility of carbon black, so that carbon black reinforcement Hysteresis loss in the rubber composition can be reduced while sufficiently exhibiting the effect.

  As the modification reaction for obtaining the first polymer and the second polymer, both solution reaction and solid phase reaction can be used, but solution reaction (even if the unreacted monomer used at the time of polymerization is included). Is good). Moreover, there is no restriction | limiting in particular about the form of this modification | denaturation reaction, You may carry out using a batch type reactor, You may carry out by a continuous type using apparatuses, such as a multistage continuous type reactor and an in-line mixer. In addition, it is important that the modification reaction is carried out after reaching the conversion rate at which the completion of the polymerization reaction is desired, and before performing a solvent removal treatment, a water treatment, a heat treatment or the like.

The temperature of the modification reaction is preferably 20 ° C. or higher, but the polymerization temperature of the conjugated diene polymer can be used as it is, and a more preferable range is 30 to 120 ° C. When the reaction temperature is lowered, the viscosity of the polymer is excessively increased and the dispersibility of the reaction product tends to be deteriorated. On the other hand, when the reaction temperature increases, the polymerization active site tends to be deactivated easily.
In addition, the usage-amount of modifier | denaturant has the preferable range of 0.25-3.0 mol with respect to 1 mol of polymerization initiators used for manufacture of a conjugated diene polymer, and the range of 0.5-1.5 mol is still more preferable. .

  In the present invention, the modification with the modifier is performed on the active site in the conjugated diene polymer, but the active site may be in the polymer molecule, and the position thereof is not particularly limited. However, the rubber obtained may include a modified conjugated diene polymer obtained by modifying at least one molecular terminal with a modifier comprising a compound containing a functional group that interacts with carbon black. From the viewpoint of the balance between the wear resistance and the low rolling resistance of the composition, it is particularly preferable. From this viewpoint, the active site in the polymer is preferably present at the terminal of the conjugated diene polymer.

  The rubber composition of the present invention contains the above-mentioned modified conjugated diene polymer (first polymer, second polymer) as a rubber component. Here, the content of the modified conjugated diene polymer in the rubber component is preferably in the range of 5 to 80 parts by mass with respect to 100 parts by mass of the rubber component. When the content of the modified conjugated diene polymer in the rubber component is less than 5 parts by mass, the carbon black dispersibility cannot be sufficiently improved. On the other hand, when the content exceeds 80 parts by mass, the workability decreases. There is. The content is more preferably in the range of 15 parts by mass or more and 60 parts by mass or less.

  In the rubber composition of the present invention, the rubber component other than the natural rubber and the modified conjugated diene polymer obtained by the above treatment includes an unmodified styrene-butadiene copolymer (SBR) and a polybutadiene rubber (BR). Polyisoprene rubber (IR), butyl rubber (IIR), ethylene-propylene copolymer and the like can be used, and among these, polyisoprene rubber is preferable. These rubber components may be used alone or as a blend of two or more.

<Carbon black for rubber compounding (high hydrogen carbon black)>
Carbon black for rubber compounding used in the present invention uses a reaction apparatus in which a combustion gas generation zone, a reaction zone, and a reaction stop zone are connected in series, and generates high-temperature combustion gas in the combustion gas generation zone, Next, the raw material is sprayed and introduced into the reaction zone to form a reaction gas flow containing carbon black, and then the reaction gas flow is quenched in the reaction stop zone by a multistage rapid refrigerant introduction means to terminate the reaction. And is manufactured as follows.

The interior of the carbon black production furnace has a structure in which a combustion zone, a reaction zone, and a reaction stop zone are connected, and the whole is covered with a refractory.
The carbon black production furnace uses a rectifying plate to rectify the oxygen-containing gas introduced from the outer periphery of the furnace head and the oxygen-containing gas introduction pipe into the flammable fluid introduction chamber as a combustion zone. An oxygen-containing gas introduction cylinder to be introduced, and a fuel oil spraying device introduction pipe installed on the central axis of the oxygen-containing gas introduction cylinder and introducing the hydrocarbon for fuel into the combustible fluid introduction chamber. In the combustion zone, high-temperature combustion gas is generated by combustion of hydrocarbons for fuel.

  The carbon black production furnace includes a reaction chamber in which a cylinder gradually converges, a raw material oil introduction chamber including, for example, four raw oil spray ports on the downstream side of the convergence chamber, and a reaction chamber on the downstream side of the raw material oil introduction chamber. With. The feed oil spray port sprays feed hydrocarbons into the hot combustion gas stream from the combustion zone. In the reaction zone, the raw material hydrocarbon is sprayed into the high-temperature combustion gas stream, and the raw material hydrocarbon is converted into carbon black by incomplete combustion or thermal decomposition reaction.

FIG. 1 is a partially longitudinal front explanatory view of an example of a carbon black production furnace for producing the rubber compounding carbon black, in which a high-temperature gas containing a carbon black raw material (raw material hydrocarbon) is introduced. The chamber 10 and the reaction continuation / cooling chamber 11 are shown. As shown in FIG. 1, the carbon black production furnace 1 includes a reaction continuation / cooling chamber 11 having a multistage rapid refrigerant introduction means 12 as a reaction stop zone. The multistage rapid refrigerant introduction means 12 sprays a rapid refrigerant such as water on the high-temperature combustion gas flow from the reaction zone. In the reaction stop zone, the high-temperature combustion gas flow is quenched by the quenching refrigerant to terminate the reaction.
The carbon black production furnace 1 may further include a device for introducing a gas body in the reaction zone or the reaction stop zone. Here, as the “gas body”, air, a mixture of oxygen and hydrocarbon, a combustion gas obtained by a combustion reaction thereof, or the like can be used.
In this way, in the production of carbon black, the average reaction temperature and residence time in each zone until the reaction gas flow enters the reaction stop zone are controlled, and the toluene color permeability X, Y and Z are set to desired values. As a result, the high hydrogen carbon black used in the present invention is obtained.

More specifically, the combustion zone is a region where a hot gas flow is generated by the reaction of fuel and air, and this downstream end is the point where feedstock is introduced into the reactor (at multiple locations). When it is introduced, it indicates the most upstream side), for example, the upstream side (left side in FIG. 1) from the point where the feedstock is introduced.
The reaction zone refers to the multistage quench water spray means 12 in the reaction continuation / cooling chamber 11 from the point where the raw material hydrocarbon is introduced (the most upstream in the case of a plurality of positions) (these means are the reaction continuation / cooling chamber). 11 can be inserted and removed freely, and the use position is selected according to the type of product to be produced and the characteristics thereof) to the point of operation (introducing a cooling medium such as water). That is, for example, when the raw material oil is introduced at the third raw material oil spray port and water is introduced by the multistage rapid refrigerant introduction means 12, the region between these becomes the reaction zone. The reaction stop zone refers to a zone below (on the right side in FIG. 1) the point where the quenching water injection spray means is operated.

In FIG. 1, the name of the reaction continuation / cooling chamber 11 is used because the reaction zone is from the raw material introduction time point to the operation time point of the quenching water injection spray means for stopping the reaction, and the reaction stop zone is thereafter. This is because the cold water introduction position may move depending on the required carbon black performance.
The high hydrogen carbon black thus obtained has the following relational expressions (1) and (2):
10 <X <40 (1)
90 <Z <100 (2)
It is necessary to satisfy.
X represents the toluene coloring permeability (%) of carbon black after the rapid refrigerant introduction from the first rapid refrigerant introduction means (12-X in FIG. 1) from the raw material introduction position, and Z represents the last Shows the toluene-colored permeability (%) of carbon black after the rapid refrigerant body is introduced by the rapid refrigerant body introducing means (12-Z in FIG. 1). That is, the carbon black after introduction of the first rapid refrigerant body has a toluene coloring permeability higher than 10% and less than 40%, and the carbon black after introduction of the final rapid refrigerant body (carbon black for rubber blending) is The toluene color transmission needs to be higher than 90% and lower than 100%. If the toluene color permeability of the carbon black for rubber blending is 90% or less, the carbon black has a lot of heavy tar components contained therein, and gives sufficient reinforcement to the rubber. Can not be done, and wear resistance is reduced.
Further, when X is 40 or more, the reinforcing property of the carbon black is lowered and the wear resistance is lowered.

The rubber compounding carbon black having such properties can be obtained by controlling the reaction temperature and residence time as described below.
That is, the residence time in the zone from when the raw material is sprayed into the reaction zone until the first quenching medium is introduced is t ₁ (seconds), and the average reaction temperature in this zone is T ₁ (° C.). And the residence time in the zone from the introduction of the first quenching medium to the introduction of the quenching medium by the second quenching medium introduction means (12-Y in FIG. 5) is t ₂ (seconds). The average reaction temperature in this zone is T ₂ (° C.), and the residence time in the zone from the introduction of the second sudden refrigerant body to the introduction of the last sudden refrigerant body (ie, the reaction stop zone) When the residence time in the zone until passage is t ₃ (seconds) and the average reaction temperature in this zone is T ₃ (° C.), the following relational expressions (3), (4) and (5)
2.00 ≦ α1 ≦ 5.00 (3)
5.00 ≦ α2 ≦ 9.00 (4)
−2.5 × (α1 + α2) + 85.0 ≦ β ≦ 90.0 (5)
(However, α1 = t ₁ × T ₁ , α2 = t ₂ × T ₂ , β = t ₃ × T _4. )
The carbon black for rubber | gum compounding can be obtained by controlling so that it may satisfy | fill.

The carbon black production furnace 1 has a structure in which thermocouples can be inserted into an arbitrary number of locations in order to monitor the temperature in the furnace. To calculate the average reaction temperature T _1, T _2, T _3, at each step (each band), at least two positions, preferably it is preferable to measure the temperature of 3-4 points.
Further, the residence times t ₁ , t ₂ , and t ₃ are calculated by calculating the volume of the introduced reaction gas fluid by a known thermodynamic calculation method, and calculating by the following equation. Note that the increase in volume due to the decomposition reaction of the feedstock oil and the rapid cooling medium is ignored.
Residence time t1 (sec) =
{Reactor passing volume from raw material hydrocarbon introduction position to first quenching medium introduction position (m ³ ) / reactive gas fluid volume (m ³ / sec)}
Residence time t ² (sec) =
{Reactor passing volume (m ³ ) / reaction gas fluid volume (m ³ / sec) from introduction of first quenching medium to introduction of second quenching medium}
Residence time t ³ (sec) =
Reactor passing volume (m ³ ) / reaction gas fluid volume (m ³ / sec) from the second quenching medium introduction position until the last quenching medium is introduced

Further, as the carbon black for rubber compounding, the following relational expressions (6), (7) and (8)
20 <X <40 (6)
50 <Y <60 (7)
90 <Z <95 (8)
(In the formula, Y represents the toluene coloring permeability of carbon black after introduction of the second quenching medium, and X and Z are the same as described above.)
What was obtained by controlling to satisfy | fill can be used suitably.
The toluene coloring transmittance is measured by the method described in Method B of Item 8 of JIS K 6218: 1997, and is expressed as a percentage with pure toluene.

The carbon black for rubber blending preferably has a hydrogen release rate exceeding 0.3% by mass. When this hydrogen release rate exceeds 0.3% by mass, the rubber composition of the present invention has high wear resistance and low heat generation. The hydrogen release rate is preferably 0.35% by mass or more. The upper limit is usually about 0.4% by mass.
The hydrogen release rate is as follows: (1) a carbon black sample is dried in a constant temperature dryer at 105 ° C. for 1 hour, cooled to room temperature in a desiccator, and (2) about 10 mg is added to a tubular tube sample container made of tin. Weigh accurately, crimp and seal, and (3) measure the amount of hydrogen gas generated when heated at 2000 ° C for 15 minutes under an argon stream with a hydrogen analyzer (Horiba EMGA621W), and display the mass fraction. .

Furthermore, the carbon black for rubber blending has a dibutyl phthalate absorption (DBP) of 95 to 220 mL / 100 g, a compressed DBP absorption (24M4DBP) of 90 to 200 mL / 100 g, and a cetyltrimethylammonium bromide adsorption specific surface area (CTAB) of 70. What is -200 m < ² > / g is preferable.
The dibutyl phthalate absorption amount (DBP) and the compressed DBP absorption amount (24M4DBP) are measured by the method described in ASTM D2414-88 (JIS K6217-4: 2001) and are absorbed per 100 g of carbon black. DBP) in mL. Further, the cetyltrimethylammonium bromide adsorption specific surface area (CTAB) is measured by the method described in JIS K6217-3: 2001 and is expressed as a specific surface area m ² / g per unit mass of carbon black.

<Rubber composition>
The rubber composition of the present invention preferably contains 5 parts by weight or more and 80 parts by weight or less of the above natural rubber with respect to the total amount of the rubber component. In particular, it is preferably 10% by mass or more, and more preferably 30% by mass or more. By including such a natural rubber, the effect of the high hydrogen carbon black is sufficiently enhanced in combination with the modified conjugated polymer.
The rubber composition of the present invention preferably contains 5 parts by weight or more and 80 parts by weight or less of the modified conjugated diene polymer based on the total amount of the rubber component. In particular, it is preferably 10% by mass or more, and more preferably 30% by mass or more. By including the modified conjugated diene polymer, the effect of the high hydrogen carbon black is sufficiently enhanced.
Examples of the rubber component include polybutadiene rubber, styrene-butadiene copolymer rubber, synthetic isoprene rubber, ethylene-propylene-diene rubber, and chloroprene rubber, in addition to the natural rubber and modified conjugated diene polymer.

Moreover, it is preferable that carbon black for rubber | gum mixing used as high hydrogen carbon black is included in the ratio of 10-250 mass parts with respect to 100 mass parts of rubber components.
In such a range, the rubber composition containing the carbon black for rubber blending having the above characteristics has desired physical properties such as wear resistance and low rolling resistance. Furthermore, the content of the high hydrogen carbon black is preferably 20 to 150 parts by mass, and more preferably 30 to 120 parts by mass with respect to 100 parts by mass of the rubber component.
The rubber compounding carbon black to be the high hydrogen carbon black is manufactured by the above-described method and has the above-described physical properties. Examples of the carbon black include FEF, SRF, HAF, and ISAF. , ISAF-LS, SAF-LS and the like.
In the rubber composition of the present invention, in addition to the rubber component and carbon black for rubber blending, other components such as inorganic filler, vulcanizing agent, vulcanization accelerator, zinc oxide, stearic acid, anti-aging agent, etc. The compounding agents normally used in the rubber industry can be appropriately selected and blended within a range not impairing the object of the present invention. As these compounding agents, commercially available products can be suitably used. The rubber composition is prepared by blending a rubber component, high hydrogen carbon black, and various appropriately selected compounding agents, kneading using a Banbury mixer, roll, internal mixer, intensive mixer, etc. It can be prepared by placing, extruding and the like.

<Tire>
The tire of the present invention is characterized in that the rubber composition is applied to any of tire members. Here, in the tire of the present invention, it is particularly preferable to use the rubber composition of the present invention for a tread. The tire using the rubber composition for a tread has excellent wear resistance and low rolling resistance and low fuel consumption. It will also be excellent in performance.
When the rubber composition of the present invention is used for a tread, for example, the rubber composition is extruded onto a tread member, and is pasted and molded by a normal method on a tire molding machine to form a raw tire. The green tire is heated and pressed in a vulcanizer to obtain a tire. In addition, as gas with which the tire of the present invention is filled, normal or air with a changed oxygen partial pressure, or an inert gas such as nitrogen is exemplified.

  Hereinafter, the present invention will be described based on examples and comparative examples, but the configuration of the present invention is not limited to the following examples.

<Examples of natural rubber production>
(1) natural rubber latex enzyme treatment steps clone species GT-1 than gathered natural rubber latex (within 1 hour after collection) and 0.4 wt% of NH ₃ by adding water adjusted to a solid concentration of 20 wt% to To a latex solution of 1000 g, phospholipase NS44151 (2,000 LEU / g, manufactured by Novozymes) was added to each of 0, 0.1, 0.5, 1.0, 5.0 with respect to 100 parts by mass of latex solids. After adding at a part by mass, stirring and dispersing, the mixture was allowed to stand for 24 hours. The latex solution was adjusted to pH 8 and reacted at room temperature (25 ° C.).

(2) Coagulation / Drying Step Next, formic acid was added to the obtained latex to adjust the pH to 4.7 to coagulate. This solid was crushed 5 times with a scraper through a shredder, and then dried with a hot air dryer at 110 ° C. for 210 minutes to obtain natural rubber.
In Table 1 below, the amount of treated enzyme, the degradation rate of phospholipid, the undegraded phospholipid, and the PRI of the natural rubber obtained were evaluated.

[Evaluation method of oxidative aging characteristics (PRI)]
The oxidative aging characteristic (PRI) is also called the residual degree of plasticity, and is calculated from the plasticity of a sample heated for 30 minutes at a high temperature (140 ° C.) and the plasticity at room temperature. The degree of plasticity was determined by compressing a disk-shaped sample at a constant load of 100 N · time 15 seconds and (thickness after compression / thickness before compression) × 100 (ISO 2930).

<Production Example of Modified Conjugated Diene Polymers 1-4>
[Modified Conjugated Diene Polymer 1]
An autoclave reactor with an internal volume of 5 liters purged with nitrogen was charged with 2750 g of cyclohexane, 0.0285 mmol of tetrahydrofuran, 375 g of 1,3-butadiene, and 2.85 mmol of n-butyllithium as a cyclohexane solution. Polymerization was carried out in a warm water bath for 4.5 hours.
When the polymerization conversion rate reached 99%, 2.08 mmol of tributyltin chloride was added and the modification reaction was performed for 15 minutes. Finally, 2,6-di-tert-butyl-p-cresol was added to the polymer solution after the reaction. Next, the solvent was removed by steam stripping, and the rubber was dried by a rip roll adjusted to 110 ° C. to obtain a modified conjugated diene polymer (1) [terminal-modified polybutadiene]. In addition, the weight average molecular weight (Mw) of polystyrene conversion by GPC of the conjugated diene polymer before modification was 510,000.

[Modified Conjugated Diene Polymer 2]
In the production of the modified conjugated diene polymer 1, a modified conjugated diene polymer 2 is obtained in the same manner as in the production of the modified conjugated diene polymer 1 except that tributyltin chloride is changed to 0.52 mmol of tin tetrachloride. It was.

[Modified Conjugated Diene Polymer 3]
In the production of the modified conjugated diene polymer 1, a modified conjugated diene polymer 3 is obtained in the same manner as in the production of the modified conjugated diene polymer 1 except that tributyltin chloride is changed to 2.08 mmol of tetraethoxysilane. It was.

[Modified Conjugated Diene Polymer 4]
In the production of the modified conjugated diene polymer 1, modified conjugated except that tributyltin chloride was changed to 2.08 mmol of N- (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propanamine. In the same manner as in the production of the diene polymer 1, a modified conjugated diene polymer 4 was obtained.

<Production example of high hydrogen carbon black>
(Production Example 1: Production of carbon black A)
Carbon black A was manufactured using the carbon black manufacturing furnace shown in FIG. However, in FIG. 1, as the multistage rapid refrigerant introduction means 12, a three-stage comprising a first rapid refrigerant introduction means 12-X, a second rapid refrigerant introduction means 12-Y, and a final rapid refrigerant introduction means 12-Z. The rapid refrigerant introduction means was used.
Moreover, in order to monitor the temperature in a manufacturing furnace, the said manufacturing furnace provided with the structure where a thermocouple can be inserted in a furnace in arbitrary several places was used. In the carbon black production furnace, A heavy oil having a specific gravity of 0.8622 (15 ° C./4° C.) was used as the fuel, and heavy oil having the properties shown in Table 2 below was used as the feed oil. The operating conditions of the carbon black production furnace and the characteristics of carbon black are shown in Table 3 below.

(Production Example 2: Production of carbon black B)
Carbon black B was produced in the same manner as in Production Example 1 except that the operating conditions shown in Table 2 below were adopted. The characteristics of this carbon black B are shown in Table 3 below.
In addition, about the characteristic of obtained carbon black A and B, dibutyl phthalate (DBP) absorption amount according to ASTM D2414-88 (JIS K6217-97), nitrogen adsorption specific surface area (according to ASTM D3037-88) N ₂ SA), specific coloring power (TINT) in accordance with ASTM D3265-88, and toluene coloring transmittance in accordance with JIS K6218-97 were measured. Further, the nitrogen adsorption specific surface area (N ₂ SA) was measured according to ASTM D3037-88, and the specific coloring power (TINT) was measured according to ASTM D3265-88.

(Examples 1-8 and Comparative Examples 1-10)
Hereinafter, rubber compositions having compositions shown in Tables 4 and 5 below were produced using the natural rubber, modified conjugated diene polymer, and carbon black.
Extracted from each production example, in Examples 1-8, the enzyme addition amount 0.5 parts by mass (phospholipase-treated natural rubber) of the production examples of the above natural rubber phospholipid-enzymatically decomposed, and 0 parts by mass in Comparative Examples 1-10 (Unprocessed natural rubber), modified conjugated diene copolymers 1 to 4 and the high hydrogen carbon blacks A and B using a Banbury mixer, the formulations shown in Table 4 and Table 5 below Each rubber composition having a formulation (compounding unit: parts by mass) was prepared.
Next, tires for tires having a tire size of 11R22.5 using these rubber compositions as treads were produced, and rolling resistance and wear resistance were evaluated by the following evaluation methods.
These results are shown in Tables 4 and 5 below.

(1) Abrasion resistance The test tire was mounted on a vehicle, and the groove weight loss at the time when the vehicle traveled 40,000 km was measured. The reciprocal of the weight loss value of the tire of Comparative Example 1 was represented as an index. The larger this value, the better the wear resistance.
(2) Rolling resistance (RR)
The running resistance when rotating freely on the drum was measured. Based on the rolling resistance value thus obtained, a rolling resistance index was determined according to the following formula. The smaller the value, the better the rolling resistance.
Rolling resistance index = (Rolling resistance value of test tire × 100) / (Rolling resistance value of tire of Comparative Example 1)

  As is apparent from the results of Tables 4 and 5, Examples 1 to 8, which are the scope of the present invention, are superior in wear resistance and rolling resistance compared to Comparative Examples 1 to 10 that are outside the scope of the present invention. It has been found.

  The rubber composition and tire of the present invention are excellent in wear resistance and rolling resistance and have high industrial applicability.

Claims (10)

A natural rubber obtained from a natural rubber latex obtained by hydrolyzing a phospholipid of a natural rubber molecule with an enzyme, and at least one selected from a silicon atom, a tin atom, a sulfur atom, an oxygen atom and a titanium atom, a polymerization active terminal, polymerization initiation A rubber component comprising a conjugated diene polymer contained in either the terminal or the polymer chain;
Using a reactor in which a combustion gas generation zone, a reaction zone, and a reaction stop zone are connected in series, high temperature combustion gas is generated in the combustion gas generation zone, and then a raw material is sprayed into the reaction zone. A carbon black for rubber compound obtained by quenching a reaction gas stream containing carbon black and terminating the reaction,
A rubber composition in which the carbon black for rubber blending satisfies the following relational expressions (1) and (2).
10 <X <40 (1)
90 <Z <100 (2)
(However, X represents the toluene coloring permeability (%) of carbon black after introduction of the first quenching medium from the raw material introduction position, and Z represents the toluene coloring permeability of carbon black after the last quenching medium introduction ( %).)   The rubber composition according to claim 1, wherein the modified conjugated diene polymer is a copolymer of an aromatic vinyl compound and a conjugated diene compound. The rubber compounding carbon black has a residence time t1 (seconds) in the zone from when the raw material is sprayed into the reaction zone until the first quenching medium is introduced, and the average reaction temperature in this zone. Is T1 (° C.), the residence time in the zone from the introduction of the first quenching medium to the introduction of the second quenching medium is t2 (seconds), and the average reaction temperature in this zone is T2 Furthermore, the residence time in the zone from the introduction of the second quenching medium to the introduction of the last quenching medium is t3 (seconds), and the average reaction temperature in this zone is T3 ( ° C), the carbon black for rubber compounding has the following relational expressions (3), (4) and (5):
2.00 ≦ α1 ≦ 5.00 (3)
5.00 ≦ α2 ≦ 9.00 (4)
−2.5 × (α1 + α2) + 85.0 ≦ β ≦ 90.0 (5)
2. The rubber composition according to claim 1, wherein the rubber composition is a high hydrogen carbon black obtained by controlling to satisfy (where α1 = t1 × T1, α2 = t2 × T2, and β = t3 × T3). The rubber compounding carbon black has the following relational expressions (6), (7) and (8):
20 <X <40 (6)
50 <Y <60 (7)
90 <Z <95 (8)
(In the formula, Y represents the toluene coloring permeability of carbon black after introduction of the second quenching medium, and X and Z are the same as described above.)
The rubber composition according to claim 1, which is obtained by controlling so as to satisfy the above.   The rubber composition according to claim 1, wherein a hydrogen release rate of the rubber compounding carbon black is higher than 0.3 mass%. Dibutyl phthalate absorption (DBP) in the rubber compounding carbon black is 95 mL / 100 g or more and 220 mL / 100 g or less, compressed DBP absorption (24M4DBP) is 90 mL / 100 g or more and 200 mL / 100 g or less, and cetyltrimethylammonium bromide The rubber composition according to claim 1, wherein the adsorption specific surface area (CTAB) is 70 m ² / g or more and 200 m ² / g or less.   The rubber composition according to claim 1, wherein the rubber composition contains 5 to 80 parts by mass of the treated natural rubber with respect to 100 parts by mass of the rubber component.   The rubber composition according to claim 1, wherein the rubber composition contains 5 parts by weight or more and 80 parts by weight or less of the modified conjugated diene polymer with respect to 100 parts by weight of the rubber component.   The rubber composition according to claim 1, wherein the rubber composition contains 10 parts by mass or more and 250 parts by mass or less of the carbon black for rubber blending with respect to 100 parts by mass of the rubber component.   A tire using the rubber composition according to any one of claims 1 to 9.

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