JPH0770368A - Rubber composition for tire sidewall - Google Patents

Abstract

(57) [Summary] [Structure] A higher α-olefin copolymer rubber [I] comprising a specific higher α-olefin, a specific aromatic ring-containing vinyl monomer, and a specific non-conjugated diene, and a diene rubber [ II], and the weight ratio [[I] / [II]] of the higher α-olefin copolymer rubber [I] and the diene rubber [II] is 5/95 to 50/50. A certain rubber composition for a tire side wall. [Effect] The rubber composition for a tire sidewall of the present invention is excellent in strength properties, weather resistance, ozone resistance, and dynamic fatigue resistance (flexing fatigue resistance), and also has adhesiveness (separation resistance). There is an effect of being excellent, and a vulcanized product having such an effect can be provided.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a rubber composition for a tire sidewall, which is excellent in strength characteristics, weather resistance, ozone resistance, dynamic fatigue resistance (flexing fatigue resistance) and adhesiveness.

[0002]

BACKGROUND OF THE INVENTION The role of the sidewall portion in a pneumatic tire is said to be to protect the carcass portion and to relieve stress or strain in the tread portion during tire running. Therefore, the characteristics of the sidewall portion required to protect the carcass portion include weather resistance with respect to ozone deterioration, external damage resistance during running on a bad road, and adhesiveness with the carcass portion with respect to separation problems of the side portion. On the other hand, the characteristics of the sidewall portion required for stress and strain relaxation of the tread portion include dynamic fatigue resistance and bending resistance. That is, since the pneumatic tire is used under various environments and conditions, various characteristics as described above are required. In addition, recently, as road maintenance has progressed and radial tires have become widespread, tire life has been extended more and more, and among the above characteristics, there is an increasing demand for improvement in dynamic fatigue resistance and weather resistance.

As a typical method for improving the dynamic fatigue resistance of rubber, the effective use of butadiene rubber (BR) is mentioned as a typical example. Japanese Patent Publication No. 57-4530 discloses syndiotactic-1,2-. Blending of polybutadiene short fibers has been proposed. However, syndiotactic-
Since the rubber containing 1,2-polybutadiene short fibers is still insufficient in terms of weather resistance, an amine anti-aging agent and a paraffin wax are usually used in combination. Amine anti-aging agents are typical ozone anti-aging agents,
Paraffin wax also has a function of forming a protective film on the surface of rubber to prevent the attack of ozone in the outside air.However, these compounding agents are used for migrating rubber during vulcanization and scattering during tire running. Consumed by etc. Therefore, in order to cope with the long life of today's tires, it is necessary to add a large amount of the ozone anti-aging agent or wax as described above, but these large amounts conversely reduce the dynamic fatigue resistance. There is a limit on the amount of compounding because they are connected. Moreover, even if the antioxidants and waxes in such general-purpose polymer rubber are optimized, the weather resistance and dynamic fatigue resistance of the grade required for the current tire sidewall cannot be completely satisfied. .

Therefore, as an approach from the viewpoint of a novel compounding technique, the use of ethylene-propylene copolymer rubber having good ozone resistance is considered. However, this ethylene-propylene copolymer rubber has a problem in its co-vulcanizability with a diene rubber and is not preferable because it causes a separation problem due to poor adhesion with a carcass rubber.

For example, US Pat. No. 4,645,793
The specification discloses the use of an ethylene / α-olefin copolymer rubber having improved weather resistance and ozone resistance. However, although the weather resistance and the ozone resistance are improved, there are problems that the dynamic fatigue resistance is lowered and the adhesion with the carcass rubber is insufficient.

Therefore, the present inventors have excellent weather resistance, ozone resistance and dynamic fatigue resistance (bending fatigue resistance), and
In order to obtain a rubber composition for tire sidewalls which is also excellent in adhesiveness (separation resistance), we have earnestly studied to obtain a specific higher α-olefin and a specific aromatic ring-containing vinyl monomer in the presence of a specific olefin polymerization catalyst. When a composition comprising a higher α-olefin copolymer rubber [I] obtained by copolymerizing a specific non-conjugated diene and a diene rubber [II] was used for a tire sidewall, this rubber composition was obtained. The inventors have found that the product is particularly excellent in the above properties and are optimal as a rubber composition for tire sidewalls, and have completed the present invention.

[0007]

SUMMARY OF THE INVENTION The present invention is intended to solve the problems associated with the prior art as described above, and is excellent in weather resistance, ozone resistance, dynamic fatigue resistance (flexing fatigue resistance), and It is an object of the present invention to provide a rubber composition for a tire sidewall, which has excellent adhesiveness (separation resistance).

[0008]

SUMMARY OF THE INVENTION A rubber composition for a tire sidewall according to the present invention comprises [I] a higher α-olefin having 6 to 20 carbon atoms, an aromatic ring-containing vinyl monomer represented by the following general formula (i), and the following: A higher α-olefin copolymer rubber consisting of a non-conjugated diene represented by the general formula (ii) and a [II] diene rubber, and a higher α-
Olefin copolymer rubber [I] and diene rubber [II]
And the weight ratio [[I] / [II]] is 5/95 to 50/50
It is characterized by being.

[0009]

[Chemical 3]

In the formula (i), n is an integer of 0 to 5 and R
¹ , R ² and R ³ each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.

[0011]

[Chemical 4]

In the formula (ii), n is an integer of 1 to 5 and R
⁴ represents an alkyl group having 1 to ⁴ carbon atoms, R ⁵ and R ⁶ represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms,
Neither R ⁵ nor R ⁶ is a hydrogen atom.

[0013]

DETAILED DESCRIPTION OF THE INVENTION The rubber composition for a tire sidewall according to the present invention will be specifically described below.

The rubber composition for a tire sidewall according to the present invention comprises a higher α-olefin copolymer rubber [I].
And a diene rubber [II]. Higher α-olefin Copolymer Rubber [I] The higher α-olefin copolymer rubber [I] used in the present invention comprises a specific higher α-olefin, a specific aromatic ring-containing vinyl monomer, and a specific aromatic ring-containing vinyl monomer. It is a copolymer in which a non-conjugated diene is present in a specific ratio.

[Higher α-Olefin] The higher α-olefin used in the present invention is a higher α-olefin having 6 to 20 carbon atoms, preferably 6 to 12 carbon atoms. Hexene-1, Heptene-1, Octene-
1, nonene-1, decene-1, undecene-1, dodecene-1,
Tridecene-1, tetradecene-1, pentadecene-1, hexadecene-1, heptadecene-1, nonadecene-1, eicosene-1,9-methyl-decene-1,11-methyl-dodecene-1,12-
Ethyl-tetradecene-1 and the like.

In the present invention, the above-mentioned higher α-
The olefin may be used alone or as a mixture of two or more kinds. Of the above-mentioned higher α-olefins, hexene-1, octene-1, and decene-1 are particularly preferably used.

[Aromatic Ring-Containing Vinyl Monomer] The aromatic ring-containing vinyl monomer used in the present invention is represented by the following general formula (i).

[0018]

[Chemical 5]

(In the formula, n is an integer of 0 to 5, and R ¹ ,
R ² and R ³ each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.) Specific examples of the aromatic ring-containing vinyl monomer include styrene, allylbenzene and 4- Phenylbutene
-1,3-phenylbutene-1,4- (4-methylphenyl) butene-1,4- (3-methylphenyl) butene-1,4- (2-methylphenyl) butene-1,4- (4 -Ethylphenyl) butene-
1,4- (4-butylphenyl) butene-1,5-phenylpentene-1,4-phenylpentene-1,3-phenylpentene-
1,5- (4-methylphenyl) pentene-1,4- (2-methylphenyl) pentene-1,3- (4-methylphenyl) pentene-1,6-phenylhexene-1,5-phenylhexene- 1,
4-phenylhexene-1,3-phenylhexene-1,6- (4-
Methylphenyl) hexene-1,5- (2-methylphenyl)
Hexene-1,4- (4-methylphenyl) hexene-1,3-
(2-Methylphenyl) hexene-1,7-phenylheptene
-1,6-phenylheptene-1,5-phenylheptene-1,4-
Phenylheptene-1,8-phenyloctene-1,7-phenyloctene-1,6-phenyloctene-1,5-phenyloctene-1,4-phenyloctene-1,3-phenyloctene-
Examples include 1,10-phenyldecene-1.

In the present invention, the above-mentioned aromatic ring-containing vinyl monomer may be used alone or as a mixture of two or more kinds. Of the above aromatic ring-containing vinyl monomers, allylbenzene and 4-phenylbutene-1
Is preferred, and 4-phenylbutene-1 is particularly preferred.

[Non-conjugated diene] The non-conjugated diene used in the present invention is represented by the following general formula (ii).

[0022]

[Chemical 6]

(In the formula, n is an integer of 1 to 5, R ⁴ is an alkyl group having 1 to 4 carbon atoms, R ⁵ and R ⁶ are hydrogen atoms or an alkyl group having 1 to 8 carbon atoms. , R ⁵
Neither R ⁶ nor R ⁶ is a hydrogen atom. ) As the non-conjugated diene as described above, specifically, 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene,
4-ethyl-1,4-hexadiene, 5-methyl-1,4-heptadiene, 5-ethyl-1,4-heptadiene, 5-methyl-1,5-heptadiene, 6-methyl-1,5-heptadiene, 5-ethyl-1,5-heptadiene, 4-methyl-1,4-octadiene, 5-methyl-1,
4-octadiene, 4-ethyl-1,4-octadiene, 5-ethyl-1,4-octadiene, 5-methyl-1,5-octadiene, 6-
Methyl-1,5-octadiene, 5-ethyl-1,5-octadiene, 6-ethyl-1,5-octadiene, 6-methyl-1,6-octadiene, 7-methyl-1,6-octadiene, 6- Ethyl-1,6-octadiene, 4-methyl-1,4-nonadiene, 5-methyl-1,4-
Nonadiene, 4-ethyl-1,4-nonadiene, 5-ethyl-1,4-
Nonadiene, 5-methyl-1,5-nonadiene, 6-methyl-1,5-
Nonadiene, 5-ethyl-1,5-nonadiene, 6-ethyl-1,5-
Nonadiene, 6-methyl-1,6-nonadiene, 7-methyl-1,6-
Nonadiene, 6-ethyl-1,6-nonadiene, 7-ethyl-1,6-
Nonadiene, 7-methyl-1,7-nonadiene, 8-methyl-1,7-
Nonadiene, 7-ethyl-1,7-nonadiene, 5-methyl-1,4-
Decadiene, 5-ethyl-1,4-decadiene, 5-methyl-1,5-
Decadiene, 6-methyl-1,5-decadiene, 5-ethyl-1,5-
Decadiene, 6-ethyl-1,5-decadiene, 6-methyl-1,6-
Decadiene, 7-methyl-1,6-decadiene, 6-ethyl-1,6-
Decadiene, 7-ethyl-1,6-decadiene, 7-methyl-1,7-
Decadiene, 8-methyl-1,7-decadiene, 7-ethyl-1,7-
Decadiene, 8-ethyl-1,7-decadiene, 8-methyl-1,8-
Decadiene, 9-methyl-1,8-decadiene, 8-ethyl-1,8-
Decadiene, 9-methyl-1,8-undecadiene and the like can be mentioned.

In the present invention, the above non-conjugated dienes may be used alone or in a mixture of two or more kinds. In addition to the non-conjugated dienes as described above, other copolymerizable monomers such as ethylene,
Propylene, butene-1, 4-methylpentene-1 and the like may be used as long as the object of the present invention is not impaired.

The molar ratio of the higher α-olefin and the aromatic ring-containing vinyl monomer constituting the higher α-olefin copolymer rubber [I] used in the present invention (higher α-olefin / aromatic ring-containing vinyl monomer) is , 30 / 70-95
/ 5, preferably 40/60 to 90/10, more preferably 50/50 to 80/20.

The value of the above molar ratio is a value obtained by measurement by the ¹³ C-NMR method. In the present invention, a higher α-olefin copolymer rubber [I] having excellent processability can be obtained by copolymerizing a higher α-olefin with an aromatic ring-containing vinyl monomer.

The content of the non-conjugated diene composing the higher α-olefin copolymer [I] used in the present invention is 0.
01 to 30 mol%, preferably 0.05 to 25 mol%,
It is particularly preferably in the range of 0.1 to 20 mol% and the iodine value is in the range of 3 to 50, preferably 5 to 40. This characteristic value is a standard value when the higher α-olefin copolymer rubber [I] of the present invention is vulcanized with sulfur or peroxide.

The higher viscosity α-olefin copolymer rubber [I] used in the present invention has an intrinsic viscosity [η] measured in a decalin solvent at 135 ° C. of 1.0 to 10.0 dl / g, preferably 1. It is in the range of 0 to 7.0 dl / g. This characteristic value is a measure showing the molecular weight of the higher α-olefin copolymer rubber [I] used in the present invention. When the molecular weight is in the above range, the weather resistance, ozone resistance, and heat aging resistance are high. It is possible to obtain a copolymer having excellent properties such as properties, low temperature characteristics, and dynamic fatigue resistance.

The higher α-used in the present invention as described above
The olefin copolymer rubber [I] can be produced by the following method. The higher α-olefin copolymer rubber [I] used in the present invention is represented by the higher α-olefin having 6 to 20 carbon atoms and the above general formula (i) in the presence of an olefin polymerization catalyst. It is obtained by copolymerizing an aromatic ring-containing vinyl polymer and a non-conjugated diene represented by the general formula (ii).

The olefin polymerization catalyst used in the present invention is composed of, for example, a solid titanium catalyst component (a), an organoaluminum compound catalyst component (b), and an electron donor catalyst component (c).

FIG. 1 shows an example of a flow chart of a method for preparing an olefin polymerization catalyst component used in producing the higher α-olefin copolymer rubber used in the present invention. The solid titanium catalyst component (a) used in the present invention is
It is a highly active catalyst component containing magnesium, titanium, halogen and an electron donor as essential components.

Such solid titanium catalyst component (a) is
It is prepared by contacting a magnesium compound, a titanium compound, and an electron donor as described below. In the present invention, examples of the titanium compound used for preparing the solid titanium catalyst component (a) include Ti (OR) g X
_4-g (R is a hydrocarbon group, X is a halogen atom, 0 ≦ g ≦
The tetravalent titanium compound represented by 4) can be mentioned.

More specifically, TiCl ₄ , TiBr ₄ ,
Titanium tetrahalides such as TiI ₄ ; Ti (OC
H ₃ ) Cl ₃ , Ti (OC ₂ H ₅ ) Cl ₃ , Ti (O-n-C ₄
H ₉ ) Cl ₃ , Ti (OC ₂ H ₅ ) Br ₃ , Ti (O-iso-C
₄ H ₉ ) Br _{3 and} other trihalogenated alkoxy titanium; T
i (OCH ₃ ) ₂ Cl ₂ , Ti (OC ₂ H ₅ ) ₂ Cl ₂ , T
_{i (O-n-C 4} H 9) 2 Cl 2, Ti (OC 2 H 5) 2 Br 2
Dihalogenated dialkoxytitanium such as; Ti (OC
H ₃ ) ₃ Cl, Ti (OC ₂ H ₅ ) ₃ Cl, Ti (O-n-C
₄ H ₉ ) ₃ Cl, monohalogenated trialkoxy titanium such as Ti (OC ₂ H ₅ ) ₃ Br; Ti (OCH ₃ ) ₄ , Ti
(OC ₂ H ₅ ) ₄ , Ti (O-n-C ₄ H ₉ ) ₄ , Ti (O-iso-
Examples thereof include tetraalkoxytitanium such as C ₄ H ₉ ) ₄ and Ti (O-2-ethylhexyl) ₄ .

Among these, halogen-containing titanium compounds,
In particular, titanium tetrahalide is preferable, and titanium tetrachloride is more preferably used. These titanium compounds may be used alone or in combination of two or more. Further, these titanium compounds may be diluted with a hydrocarbon compound or a halogenated hydrocarbon compound.

In the present invention, examples of the magnesium compound used for preparing the solid titanium catalyst component (a) include a reducing magnesium compound and a non-reducing magnesium compound.

Examples of the reducing magnesium compound include magnesium compounds having a magnesium-carbon bond or a magnesium-hydrogen bond. Specific examples of such reducing magnesium compounds include dimethyl magnesium, diethyl magnesium, dipropyl magnesium, dibutyl magnesium, diamyl magnesium, dihexyl magnesium, didecyl magnesium, ethyl magnesium chloride, propyl magnesium chloride, butyl. Magnesium chloride, hexyl magnesium chloride, amyl magnesium chloride, butyl ethoxy magnesium, ethyl butyl magnesium, octyl butyl magnesium,
Butyl magnesium halide and the like can be mentioned. These magnesium compounds may be used alone or may form a complex compound with an organoaluminum compound described later. Further, these magnesium compounds may be liquid or solid.

Specific examples of the magnesium compound having no reducing property include magnesium halides such as magnesium chloride, magnesium bromide, magnesium iodide and magnesium fluoride; magnesium methoxy chloride, magnesium ethoxy chloride, magnesium isopropoxy chloride. Alkoxy magnesium halides such as butoxy magnesium chloride and octoxy magnesium chloride; Alkoxy magnesium halides such as phenoxy magnesium chloride and methylphenoxy magnesium chloride; Ethoxy magnesium, isopropoxy magnesium, butoxy magnesium, n-octoxy magnesium, 2-ethylhexoxy magnesium Alkoxy magnesium such as;
Examples thereof include allyloxymagnesium such as phenoxymagnesium and dimethylphenoxymagnesium; and magnesium carboxylates such as magnesium laurate and magnesium stearate.

The non-reducing magnesium compound may be a compound derived from the above-mentioned reducing magnesium compound or a compound derived during preparation of the catalyst component. In order to derive a non-reducing magnesium compound from a reducible magnesium compound, for example, a reducible magnesium compound is prepared from polysiloxane compounds, halogen-containing silane compounds, halogen-containing aluminum compounds, esters, alcohols, etc. It may be brought into contact with the compound.

In the present invention, the magnesium compound may be a complex compound, a compound compound or a complex compound of the above magnesium compound with another metal, in addition to the above-mentioned reducing magnesium compound and non-reducing magnesium compound. It may be a mixture with a metal compound. Further, it may be a mixture of two or more kinds of the above compounds.

In the present invention, among these, a magnesium compound having no reducing property is preferable, a halogen-containing magnesium compound is particularly preferable, and among these, magnesium chloride, alkoxy magnesium chloride, and allyloxy magnesium chloride are preferably used. To be

In the present invention, examples of the electron donor used in the preparation of the solid titanium catalyst component (a) include organic carboxylic acid esters and polyvalent carboxylic acid esters which will be described later. Specifically, they are represented by the following formula. And a compound having a skeleton.

[0042]

[Chemical 7]

In the above formula, R ¹ represents a substituted or unsubstituted hydrocarbon group, R ² , R ⁵ and R ⁶ represent a hydrogen atom, a substituted or unsubstituted hydrocarbon group, and R ³ and R ⁴ Represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group. At least one of R ³ and R ⁴ is preferably a substituted or unsubstituted hydrocarbon group. R ³ and R ⁴ may be connected to each other to form a ring structure. Examples of the substituted hydrocarbon group include substituted hydrocarbon groups containing a hetero atom such as N, O and S, and examples thereof include -COC- and-.
_{COOR, -COOH, -OH, -SO 3} H, -C-N
-C -, - and hydrocarbon group substituted with a structure such as NH _2.

Of these, a diester derived from a dicarboxylic acid in which at least one of R ¹ and R ² is an alkyl group having 2 or more carbon atoms is preferable. Specific examples of the polycarboxylic acid ester include diethyl succinate, dibutyl succinate, diethyl methyl succinate, diisobutyl α-methyl glutarate, dibutyl methyl malonate, diethyl malonate, diethyl ethyl malonate, diethyl isopropyl malonate, butyl. Diethyl malonate, diethyl phenylmalonate, diethyl diethylmalonate, diethyl allylmalonate, diethyl diisobutylmalonate,
Di-n-butylmalonate diethyl, dimethyl maleate, monooctyl maleate, diisooctyl maleate, diisobutyl maleate, diisobutyl butyl maleate, diethyl butyl maleate, diisopropyl β-methyl glutarate, diallyl ethyl succinate, di-2 fumarate. -Fatty acid polycarboxylic acid esters such as ethylhexyl, diethyl itaconic acid, diisobutyl itaconic acid, diisooctyl citraconic acid, dimethyl citraconic acid; diethyl 1,2-cyclohexanecarboxylate, diisobutyl 1,2-cyclohexanecarboxylic acid, diethyl tetrahydrophthalate, nadic Aliphatic polycarboxylic acid ester such as acid diethyl; monoethyl phthalate, dimethyl phthalate, methyl ethyl phthalate, monoisobutyl phthalate, diethyl phthalate, Ethyl isobutyl tartrate, mono-n-butyl phthalate, ethyl n-butyl phthalate, di-n-propyl phthalate, diisopropyl phthalate, di-n-butyl phthalate, diisobutyl phthalate, di-n-heptyl phthalate, phthalic acid Di-2-ethylhexyl, didecyl phthalate, benzyl butyl phthalate, diphenyl phthalate, diethyl naphthalene dicarboxylate, dibutyl naphthalene dicarboxylate, triethyl trimellitate,
Examples thereof include aromatic polycarboxylic acid esters such as dibutyl trimellitate; esters derived from heterocyclic polycarboxylic acids such as 3,4-furandicarboxylic acid.

Other examples of the polycarboxylic acid ester include diethyl adipate, diisobutyl adipate, diisopropyl sebacate, di-n-butyl sebacate, n-octyl sebacate, di-2-ethylhexyl sebacate and the like. The ester derived from the long-chain dicarboxylic acid of

Among these polyvalent carboxylic acid esters,
A compound having a skeleton represented by the above-mentioned general formula is preferable, more preferably an ester derived from phthalic acid, maleic acid, substituted malonic acid and the like and an alcohol having 2 or more carbon atoms, and phthalic acid and a carbon atom. Number 2
Diesters obtained by the reaction with the above alcohols are particularly preferable.

As the polyvalent carboxylic acid ester, it is not always necessary to use the polyvalent carboxylic acid ester as described above as a starting material, and the polyvalent carboxylic acid ester may be used in the process of preparing the solid titanium catalyst component (a). A compound capable of inducing an ester may be used to form a polyvalent carboxylic acid ester in the step of preparing the solid titanium catalyst component (a).

In the present invention, the electron donors other than the polyvalent carboxylic acid which can be used when preparing the solid titanium catalyst component (a) include alcohols, amines, amides, as described below. Ethers, ketones, nitriles, phosphines, stipines, arsines, phosphoramides, esters, thioethers,
Organosilicon compounds such as thioesters, acid anhydrides, acid halides, aldehydes, alcoholates, and alkoxy (aryloxy) silanes, organic acids, and amides of metals belonging to Groups I to IV of the periodic table And salts.

In the present invention, the solid titanium catalyst component (a) can be produced by bringing the above-mentioned magnesium compound (or metallic magnesium), electron donor and titanium compound into contact with each other. In order to produce the solid titanium catalyst component (a), a known method of preparing a highly active titanium catalyst component from a magnesium compound, a titanium compound and an electron donor can be adopted. The above components may be contacted in the presence of other reaction reagents such as silicon, phosphorus and aluminum.

The production method of these solid titanium catalyst components (a) will be briefly described below with some examples. (1) A method of reacting a magnesium compound or a complex compound composed of a magnesium compound and an electron donor with a titanium compound in a liquid phase.

This reaction may be carried out in the presence of a grinding aid or the like. Further, when the reaction is performed as described above, the solid compound may be pulverized. Furthermore, each component may be pretreated with an electron donor and / or a reaction aid such as an organoaluminum compound or a halogen-containing silicon compound when the reaction is carried out as described above. In addition,
In this method, the electron donor is used at least once. (2) Liquid magnesium compound having no reducing property,
A method of reacting a liquid titanium compound in the presence of an electron donor to deposit a solid titanium composite agent. (3) A method of further reacting the reaction product obtained in (2) with a titanium compound. (4) In the reaction product obtained in (1) or (2),
A method of further reacting an electron donor and a titanium compound. (5) A solid compound obtained by pulverizing a magnesium compound or a complex compound composed of a magnesium compound and an electron donor in the presence of a titanium compound is treated with halogen, a halogen compound or an aromatic hydrocarbon. Method. In this method, the magnesium compound or the complex compound composed of the magnesium compound and the electron donor may be ground in the presence of a grinding aid. Alternatively, the magnesium compound or the complex compound composed of the magnesium compound and the electron donor may be pulverized in the presence of the titanium compound, pretreated with a reaction aid, and then treated with halogen or the like. Examples of the reaction aid include organic aluminum compounds and halogen-containing silicon compounds. In this method, the electron donor is used at least once. (6) A method of treating the compound obtained in (1) to (4) above with halogen, a halogen compound, or an aromatic hydrocarbon. (7) A method of bringing a reaction product of a metal acid compound, dihydrocarbyl magnesium and a halogen-containing alcohol into contact with an electron donor and a titanium compound. (8) A method of reacting a magnesium compound such as a magnesium salt of an organic acid, alkoxy magnesium, or aryloxy magnesium with an electron donor, a titanium compound and / or a halogen-containing hydrocarbon.

Among the methods for preparing the solid titanium catalyst component (a) described in (1) to (8) above, a method using a liquid titanium halide during the catalyst preparation, a method using a titanium compound, or titanium is used. When using the compound, a method using a halogenated hydrocarbon is preferable.

The amount of each of the above-mentioned components used in preparing the solid titanium catalyst component (a) varies depending on the preparation method and cannot be specified unconditionally. For example, the amount of electron donor is about 1 mol per mol of the magnesium compound. 0.01-5
The amount of the titanium compound is about 0.01 to 500 mol, preferably 0.05 to 30 mol, preferably in an amount of 0.05 to 2 mol.
Used in an amount of 0 mol.

The solid titanium catalyst component (a) thus obtained contains magnesium, titanium, halogen and an electron donor as essential components. In this solid titanium catalyst component (a), the halogen / titanium (atomic ratio) is about 4-200, preferably about 5-100,
The electron donor / titanium (molar ratio) is about 0.1-10,
Desirably, it is about 0.2 to about 6, and the magnesium / titanium (atomic ratio) is about 1 to 100, preferably about 2 to 50.

The solid titanium catalyst component (a) contains a magnesium halide having a smaller crystal size than that of a commercially available magnesium halide, and usually has a specific surface area of about 50 m ² / g or more, preferably about 60 to 1000 m ^2. / G,
More preferably, it is about 100 to 800 m ² / g. Since the solid titanium catalyst component (a) forms the catalyst component by integrating the above components, the composition thereof is not substantially changed by washing with hexane.

Such solid titanium catalyst component (a) is
Although it can be used alone, it can also be used by diluting it with an inorganic compound or an organic compound such as a silicon compound, an aluminum compound or a polyolefin. When a diluent is used, it exhibits high catalytic activity even if it has a specific surface area smaller than that described above.

The preparation method of such a high activity titanium catalyst component is described in, for example, JP-A-50-108385 and JP-A-5-108385.
0-126590, 51-20297, 51-28189, 51-64586, 51-92885, 51-13662.
No. 5, gazette 52-87489 gazette, gazette 52-100596 gazette, gazette 52
-147688, 52-104593, 53-2580, 53-40093, 53-40094, 53-43094
No. 55, No. 55-135102, No. 55-135103, No. 55
-152710, 56-811, 56-11908,
56-18606, 58-83006, 58-138705, 58-138706, 58-138707, 58-1.
38708, 58-138709, 58-138710, 58-138715, 60-23404, 61-2110
No. 9, No. 61-37802, No. 61-37803.

As the organoaluminum compound catalyst component (b) used in the present invention, a compound having at least one aluminum-carbon bond in the molecule can be used.
Such compounds include, for example, (a) general formula (R ¹ ) m Al (O (R ² )) n Hp Xq (wherein R ¹ and R ² have usually 1 to 15 carbon atoms, preferably Is a hydrocarbon group containing 1 to 4, which may be the same or different from each other, X represents a halogen atom, 0 <m ≦ 3, n is 0 ≦ n <3, and p is 0 ≦ p <3. , Q
Is a number 0 ≦ q <3, and m + n + p + q = 3
An organic aluminum compound represented by the formula: (b) a general formula (M ¹ ) Al (R ¹ ) ₄ (wherein M ¹ is Li, Na, K, and R ¹ is the same as above) Examples thereof include complex alkylated products of a Group 1 metal and aluminum.

Examples of the organoaluminum compound belonging to the above item (a) include the following compounds. General formula (R ¹ ) n Al (O (R ² )) _3-m (wherein R ¹ and R ² are the same as above. M is preferably a number of 1.5 ≦ m ≦ 3), Formula (R ¹ ) m AlX _3-m (wherein R ¹ is the same as described above, X is halogen, and m is preferably 0 <m <3), general formula (R ¹ ) m AlH _3-m ( In the formula, R ¹ is the same as above, and m is preferably 2 ≦ m <3.
Of the general formula (R ¹ ) m Al (OR ² ) n Xq (wherein R ¹ and R ² are the same as above. X is halogen, 0
<M ≦ 3, 0 ≦ n <3, 0 ≦ q <3, and m + n + q = 3
And the like.

Specific examples of the aluminum compound belonging to (a) include trialkyl aluminum such as triethyl aluminum and tributyl aluminum; trialkenyl aluminum such as triisoprenyl aluminum; diethyl aluminum ethoxide and dibutyl aluminum butoxide. Dialkyl aluminum alkoxide; ethyl aluminum sesquiethoxide,
Alkyl aluminum sesquialkoxides such as butyl aluminum sesquibutoxide, (R ¹ ) _2.5 Al (O
(R ² )) Partially alkoxylated alkylaluminum having an average composition represented by _0.5 or the like; Dialkylaluminum halides such as diethylaluminum chloride, dibutylaluminum chloride, diethylaluminum bromide; Ethylaluminum sesquichloride, butylaluminum sesquichloride Alkyl aluminum sesquihalides such as ethyl aluminum sesquibromide; partially halogenated alkyl aluminums such as alkyl aluminum dihalides such as ethyl aluminum dichloride, propyl aluminum dichloride and butyl aluminum dibromide; diethyl aluminum hydride, dibutyl aluminum hydride Dialkyl aluminum hydride such as; ethyl aluminum dihydride, Partially hydrogenated alkylaluminums such as alkylaluminum dihydrides such as ropylaluminium dihydride; partially alkoxylated and halogenated such as ethylaluminum ethoxy chloride, butylaluminum butoxycyclolide, ethylaluminum ethoxy bromide Alkyl aluminum can be mentioned.

As a compound similar to (a) above
Is 2 or more aluminum via oxygen atom or nitrogen atom
Can include organoaluminum compounds bound to
It Examples of such a compound include (C₂H_Five)₂
AlOAl (C₂H_Five)₂, (C_FourH₉)₂AlOAl (C_Four
H₉)₂, (C ₂H_Five)₂AlN (C₂H_Five) Al (C
₂H_Five)₂, Methylaminooxane, etc.
Wear.

As the compound belonging to (b) above, Li
Al (C₂H_Five)_Four, LiAl (C₇H ₁₅)_FourGive up
be able to. Among these, especially trialkylal
Minium or two or more aluminum compounds mentioned above
It is preferable to use an alkylaluminum having a bound substance.
Good

The electron donor catalyst component (c) includes oxygen-containing alcohols such as alcohols, phenols, ketones, aldehydes, carboxylic acids, esters of organic or inorganic acids, ethers, acid amides, acid anhydrides and alkoxysilanes. An electron donor, a nitrogen-containing electron donor such as ammonia, amine, nitrile, or isocyanate, or the polyvalent carboxylic acid ester as described above can be used.

More specifically, carbon such as methanol, ethanol, propanol, pentanol, hexanol, octanol, dodecanol, octadecyl alcohol, oleyl alcohol, benzyl alcohol, phenylethyl alcohol, cumyl alcohol, isopropyl alcohol and isopropylbenzyl alcohol. Alcohols having 1 to 18 atoms; phenol, cresol, xylenol, ethylphenol, propylphenol,
6 to 20 carbon atoms which may have a lower alkyl group, such as nonylphenol, cumylphenol and naphthol
Phenols; acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone, benzoquinone, and other ketones having 3 to 15 carbon atoms;
Aldehydes having 2 to 15 carbon atoms such as acetaldehyde, propionaldehyde, octylaldehyde, benzaldehyde, tolualdehyde, naphthaldehyde; methyl formate, methyl acetate, ethyl acetate, vinyl acetate, propyl acetate, octyl acetate, cyclohexyl acetate, propionic acid. Ethyl, methyl butyrate, ethyl valerate, methyl chloroacetate, ethyl dichloroacetate, methyl methacrylate, ethyl crotonate, ethyl cyclohexanecarboxylate, methyl benzoate, ethyl benzoate, propyl benzoate, butyl benzoate, octyl benzoate, Cyclohexyl benzoate, phenyl benzoate, benzyl benzoate, methyl toluate, ethyl toluate, amyl toluate, ethyl ethyl benzoate, methyl anisate, -n-butyl maleate, methylmalon Diisobutyl, cyclohexene carboxylic di -n- hexyl, nadic diethyl, tetrahydrophthalic acid diisopropyl, diethyl phthalate, diethyl phthalate, diisobutyl phthalate, di -n
-Butyl, di-2-ethylhexyl phthalate, γ-butyrolactone, δ-valerolactone, coumarin, phthalide, ethylene carbonate and other organic acid esters having 2 to 30 carbon atoms;
Acid halides having 2 to 15 carbon atoms such as acetyl chloride, benzoyl chloride, toluic acid chloride and anisic acid chloride; number of carbon atoms such as methyl ether, ethyl ether, isopropyl ether, butyl ether, amyl ether, tetrahydrofuran, anisole and diphenyl ether 2 to 20 ethers; acid amides such as acetic acid amide, benzoic acid amide, toluic acid amide; methylamine, ethylamine, diethylamine, tributylamine, piperidine, tribenzylamine, aniline, pyridine, picoline, tetramethylenediamine, etc. Amines; nitriles such as acetonitrile, benzonitrile, tolunitrile; acid anhydrides such as acetic anhydride, phthalic anhydride, benzoic anhydride, etc. are used.

As the electron donor (c), an organosilicon compound represented by the following general formula [1] can be used. Rn Si (OR ') _4-n ... [1] (In the formula, R and R'are hydrocarbon groups, and n is 0 <n.
It is a number that satisfies <4. ) Specific examples of the organosilicon compound represented by the above general formula [1] include trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane,
Dimethyldiethoxysilane, diisopropyldimethoxysilane, t-butylmethyldimethoxysilane, t-butylmethyldiethoxysilane, t-amylmethyldiethoxysilane, diphenyldimethoxysilane, phenylmethyldimethoxysilane, diphenyldiethoxysilane, bis-o-tolyl Dimethoxysilane, bis-m-tolyldimethoxysilane, bis-p-tolyldimethoxysilane, bis-p-tolyldiethoxysilane, bisethylphenyldimethoxysilane,
Dicyclohexyldimethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, methyltrimethoxysilane, n-propyltriethoxysilane, decyltrimethoxysilane, decyltriethoxysilane Silane, phenyltrimethoxysilane, γ-chloropropyltrimethoxysilane, methyltoluethoxysilane, ethyltriethoxysilane, vinyltriethoxysilane, t-butyltriethoxysilane, n-butyltriethoxysilane, iso-
Butyltriethoxysilane, phenyltriethoxysilane, γ-aminopropyltriethoxysilane, chlorotriethoxysilane, ethyltriisopropoxysilane,
Vinyltributoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, 2-norbornanetrimethoxysilane, 2-norbornanetriethoxysilane, 2-norbornanemethyldimethoxysilane,
Ethyl silicate, butyl silicate, trimethylphenoxysilane, methyltriallyloxy silane, vinyltris (β-methoxyethoxysilane), vinyltriacetoxysilane, dimethyltetraethoxydisiloxane and the like are used.

Of these, ethyltriethoxysilane, n-propyltriethoxysilane, t-butyltriethoxysilane, vinyltriethoxysilane, phenyltriethoxysilane, vinyltributoxysilane, diphenyldimethoxysilane, phenylmethyldimethoxysilane, bis-p -
Tolyldimethoxysilane, p-tolylmethyldimethoxysilane, dicyclohexyldimethoxysilane, cyclohexylmethyldimethoxysilane, 2-norbornanetriethoxysilane, 2-norbornanemethyldimethoxysilane,
Diphenyldiethoxysilane is preferred.

Further, as the electron donor catalyst component (c),
It is also possible to use an organosilicon compound represented by the following general formula [2]. SiR ¹ R ² m (OR ³ ) _3-m ... [2] (In the formula, R ¹ is a cyclopentyl group or a cyclopentyl group having an alkyl group, and R ² is an alkyl group, a cyclopentyl group or an alkyl group. It is a group selected from the group consisting of a cyclopentyl group, R ³ is a hydrocarbon group, and m is a number satisfying 0 ≦ m ≦ 2.) In the above formula [2], R ¹ is a cyclopentyl group or an alkyl group. R ¹ has an alkyl group such as a 2-methylcyclopentyl group, a 3-methylcyclopentyl group, a 2-ethylcyclopentyl group, and a 2,3-dimethylcyclopentyl group, in addition to the cyclopentyl group. A cyclopentyl group can be mentioned.

In the formula [2], R ² is any one of an alkyl group, a cyclopentyl group or a cyclopentyl group having an alkyl group, and R ² is, for example, a methyl group, an ethyl group, a propyl group or an isopropyl group. Group, butyl group, allyl group such as hexyl group, or R ¹
The cyclopentyl group and the cyclopentyl group having an alkyl group exemplified as can be mentioned in the same manner.

In the formula [2], R ³ is a hydrocarbon group, and examples of R ³ include hydrocarbon groups such as an alkyl group, a cycloalkyl group, an aryl group and an aralkyl group.

Among these, it is preferable to use an organosilicon compound in which R ¹ is a cyclopentyl group, R ² is an alkyl group or a cyclopentyl group, and R ³ is an alkyl group, particularly a methyl group or an ethyl group.

Specific examples of such an organosilicon compound include trialkoxysilanes such as cyclopentyltrimethoxysilane, 2-methylcyclopentyltrimethoxysilane, 2,3-dimethylcyclopentyltrimethoxysilane, and cyclopentyltriethoxysilane; Dialkoxysilanes such as dicyclopentyldimethoxysilane, bis (2-methylcyclopentyl) dimethoxysilane, bis (2,3-dimethylcyclopentyl) dimethoxysilane, dicyclopentyldiethoxysilane; tricyclopentylmethoxysilane, tricyclopentylethoxysilane,
Examples thereof include monoalocoxysilanes such as dicyclopentylmethylmethoxysilane, dicyclopentylethylmethoxysilane, dicyclopentylmethylethoxysilane, cyclopentyldimethylmethoxysilane, cyclopentyldiethylmethoxysilane, and cyclopentyldimethylethoxysilane. Among these electron donors, organic carboxylic acid esters or organic silicon compounds are preferable, and organic silicon compounds are particularly preferable.

The olefin polymerization catalyst used in the present invention is formed from the solid titanium catalyst component (a) as described above, the organoaluminum compound catalyst component (b), and the electron donor catalyst component (c). According to the present invention, the olefin polymerization catalyst is used to polymerize a higher α-olefin, an aromatic ring-containing vinyl monomer, and a non-conjugated diene. -After prepolymerizing an olefin, a higher α-olefin, an aromatic ring-containing vinyl monomer, and a non-conjugated diene can be polymerized (main polymerization) using this catalyst.

In the prepolymerization, a catalyst having a much higher concentration than the catalyst concentration in the system in the main polymerization can be used.
The concentration of the solid titanium catalyst component (a) in the prepolymerization is
It is usually about 0.01 to 200 mmol, preferably about 0.1 to 100 mmol, and particularly preferably 1 to 5 in terms of titanium atom per liter of an inert hydrocarbon medium described later.
It is desirable to set it in the range of 0 mmol.

The amount of the organoaluminum catalyst component (b) is
The amount may be such that 0.1 to 500 g, preferably 0.3 to 300 g of polymer is produced per 1 g of the solid titanium catalyst component (a), and it is per mol of titanium atom in the solid titanium catalyst component (a). The amount is usually about 0.1 to 100 mol, preferably about 0.5 to 50 mol, particularly preferably 1 to 20 mol.

The electron donor catalyst component (c) is contained in an amount of 0.1 to 5 per mol of titanium atom in the solid titanium catalyst component (a).
It is preferably used in an amount of 0 mol, preferably 0.5 to 30 mol, particularly preferably 1 to 10 mol.

The prepolymerization is preferably carried out under mild conditions by adding an olefin or higher α-olefin and the above catalyst component to an inert hydrocarbon medium. Examples of the inert hydrogen medium used in this case include aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane, and kerosene; cyclopentane, cyclohexane, methylcyclopentane, etc. Examples thereof include alicyclic hydrocarbons; aromatic hydrocarbons such as benzene, toluene and xylene; halogenated hydrocarbons such as ethylene chloride and chlorobenzene; and mixtures thereof. Of these inert hydrocarbon media, it is particularly preferable to use aliphatic hydrocarbons.
The olefin or higher α-olefin itself may be prepolymerized in a solvent, or may be prepolymerized in a substantially solvent-free state.

The higher α-olefin used in the prepolymerization may be the same as or different from the higher α-olefin used in the main polymerization described later. The reaction temperature in the prepolymerization is usually about −20 to + 100 ° C., preferably about −2.
It is desirable that the temperature is in the range of 0 to + 80 ° C, more preferably 0 to + 40 ° C.

A molecular weight modifier such as hydrogen may be used in the prepolymerization. Such a molecular weight modifier has an intrinsic viscosity [η] of a polymer obtained by prepolymerization measured in a decalin solvent at 135 ° C. of about 0.2 or less.
It is desirable to use it in an amount of dl / g or more, preferably about 0.5 to 10 dl / g.

The prepolymerization is carried out so that about 0.1 to 500 g, preferably about 0.3 to 300 g, particularly preferably 1 to 100 g of a polymer is produced per 1 g of the solid titanium catalyst component (a), as described above. It is desirable to do this. If the prepolymerization amount is too large, the production efficiency of the olefin polymer may decrease.

The prepolymerization can be carried out batchwise or continuously. The solid titanium catalyst component (a) or the solid titanium catalyst component (a) obtained by prepolymerizing the olefin polymerization catalyst as described above, the organoaluminum catalyst component (b), and the electron donor catalyst component ( in the presence of an olefin polymerization catalyst formed from
Copolymerization (main polymerization) of an olefin, an aromatic ring-containing vinyl monomer, and a non-conjugated diene is performed.

In the copolymerization (main polymerization) of a higher α-olefin, an aromatic ring-containing vinyl monomer and a non-conjugated diene, in addition to the above-mentioned olefin polymerization catalyst, an olefin polymerization as an organoaluminum compound catalyst component is carried out. The same thing as the organoaluminum compound catalyst component (b) used when producing the catalyst for use can be used. Also high-class α
-An electron donor catalyst used in producing an olefin polymerization catalyst as an electron donor catalyst component in the copolymerization (main polymerization) of an olefin, an aromatic ring-containing vinyl monomer, and a non-conjugated diene The same thing as the component (c) can be used. In addition, the organoaluminum compound and the electron donor used in the copolymer (main polymerization) of the higher α-olefin, the aromatic ring-containing vinyl monomer and the non-conjugated diene do not necessarily prepare the above-mentioned olefin polymerization catalyst. It need not be the same as the organoaluminum compound and electron donor used in the process.

The copolymerization (main polymerization) of the higher α-olefin, the aromatic ring-containing vinyl monomer and the non-conjugated diene is usually carried out in the liquid phase. As the reaction medium for the main polymerization, the above-mentioned inert hydrocarbon medium may be used, or an olefin which is liquid at the reaction temperature may be used.

In the copolymerization (main polymerization) of the higher α-olefin, the aromatic ring-containing vinyl monomer and the non-conjugated diene, the solid titanium catalyst component (a) is converted into titanium atom per liter of polymerization volume, Usually, it is used in an amount of about 0.001 to about 1.0 mmol, preferably about 0.005 to 0.5 mmol. Further, the organoaluminum catalyst component (b) is the organoaluminum compound catalyst component (b) based on 1 mol of titanium atom in the solid titanium catalyst component (a).
The metal atom therein is usually used in an amount of about 1 to 2000 mol, preferably about 5 to 500 mol. Further, the electron donor catalyst component (c) is usually about 0.001 to 10 mol, preferably 0.01 to 2 mol, per mol of the metal atom in the organoaluminum compound catalyst component (b).
It is particularly preferably used in an amount of 0.05 to 1 mol.

If hydrogen is used during the main polymerization, the molecular weight of the resulting polymer can be adjusted. In the present invention, the polymerization temperature of the higher α-olefin, the aromatic ring-containing vinyl monomer and the non-conjugated diene is usually about 20 to 20.
0 ° C., to preferably about 40 to 100 ° C., the pressure is usually preferably atmospheric pressure to 100 kg / cm ² is set to the normal pressure to 50 kg / cm ^2. In the copolymerization (main polymerization) of the higher α-olefin, the aromatic ring-containing vinyl monomer and the non-conjugated diene, the polymerization can be carried out by any of a batch system, a semi-continuous system and a continuous system. Further, the polymerization can be carried out in two or more stages by changing the reaction conditions.

Diene rubber [II] The diene rubber [II] used in the present invention is a conventionally known diene rubber, and specifically, natural rubber, isoprene rubber, SBR, BR, CR, NBR and the like. Is mentioned.

As the natural rubber, the Green Book (natural
Standardized by international quality packaging standards for various grades of rubber
Natural rubber is commonly used. Also with isoprene rubber
Has a specific gravity of 0.91 to 0.94 and a Mooney viscosity.
Degree [ML_{1 + 4}(100 ° C.)] is 30 to 120
Plain rubber is generally used, and SBR has a specific gravity of
0.91 to 0.98, and Mooney viscosity [ML
_{1 + 4}(100 ° C.)] is generally 20 to 120.
Used for.

As for BR, the specific gravity is 0.90 to 0.
A BR having a Mooney viscosity [ML 1 _{+ 4} (100 ° C.)] of 20 to 120 is generally used. In the present invention, the above-mentioned diene rubber may be used alone or as a mixture of two or more kinds.

Of the above diene rubbers, natural rubber, isoprene rubber, SBR, BR or a mixture thereof is preferably used. Blending Ratio The blending ratio of the higher α-olefin copolymer rubber [I] and the diene rubber [II] constituting the rubber composition for tire sidewall according to the present invention is [[I] / [ I
I]] is 5/95 to 50/50, preferably 10/90
~ 40/60, more preferably 10/90 to 30/7
It is 0.

The rubber composition for a tire sidewall according to the present invention can be produced by adopting a known rubber-like polymer mixing method such as a mixing method in a mixer such as a Banbury mixer. Further, in the present invention, a usual rubber compounding agent is used when compounding rubber. Such compounding agents include rubber reinforcing agents such as carbon black and finely divided silicic acid; softening agents; fillers such as light calcium carbonate, heavy calcium carbonate, talc, clay and silica;
Examples include tackifiers, waxes, binding resins, zinc oxide, antioxidants, antiozonants, processing aids and vulcanization activators. These compounding agents may be used alone or in combination of two or more.

The vulcanization activator is generally preferably added in the second stage of compounding. The operation of the second stage of compounding is usually about 6
It is recommended to use a Banbury mixer whose temperature does not exceed 0 ° C. The vulcanization activator may be sulfur or sulfur containing various accelerators.

The vulcanized product of the rubber composition for a tire sidewall according to the present invention comprises the above-mentioned higher α-olefin copolymer rubber [I], a diene rubber (ii) and a compounding agent. 5 to a temperature of 150 ° C to 200 ° C.
It can be obtained by adopting an ordinary vulcanization method of heating for 60 minutes to vulcanize.

[0092]

The rubber composition for a tire sidewall according to the present invention has a higher α-olefin copolymer rubber [I].
And diene rubber [II] in a specific ratio, it has excellent strength properties, weather resistance, ozone resistance, and dynamic fatigue resistance (flexing fatigue resistance), as well as adhesion (separation resistance). A vulcanized product having such an effect can be provided.

[0093]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[0094]

Examples 1 to 6 and Comparative Examples 1 and 2 (Preparation of solid titanium catalyst component (a)) 95.2 g of anhydrous magnesium chloride, 442 ml of decane and 390.6 g of 2-ethylhexyl alcohol were heated at 130 ° C. for 2 hours. After carrying out a uniform solution, 21.3 g of phthalic anhydride was added to this solution, and the mixture was further stirred and mixed at 130 ° C. for 1 hour to dissolve phthalic anhydride in this uniform solution. After cooling the homogeneous solution thus obtained to room temperature, 200 ml of titanium tetrachloride having 75 ml maintained at -20 ° C.
The entire amount was added dropwise into the flask over 1 hour. After charging,
The temperature of this mixed solution was raised to 110 ° C. over 4 hours, and 1
When the temperature reached 10 ° C, diisobutyl phthalate 5.2
2 g was added, and the mixture was kept at the same temperature for 2 hours with stirring. After completion of the reaction for 2 hours, a solid portion was collected by hot filtration,
This solid portion was resuspended in 275 ml of titanium tetrachloride, and then heated and reacted again at 110 ° C. for 2 hours. After the reaction was completed, the solid portion was collected again by hot filtration, and thoroughly washed with decane and hexane at 110 ° C. until no free titanium compound was detected in the washing liquid. The titanium catalyst component (a) prepared by the above operation was stored as a decane slurry, and a part of this was dried for the purpose of examining the catalyst composition. The composition of the titanium catalyst component (a) thus obtained was as follows: titanium 2.5% by weight, chlorine 65% by weight,
It was 19% by weight of magnesium and 13.5% by weight of diisobutyl phthalate. (Polymerization) Using a 4-liter glass polymerization vessel equipped with a stirring blade, hexene-1,4-phenylbutene-1,
A copolymerization reaction with 7-methyl-1,6-octadiene was performed.

That is, from the top of the polymerization vessel, hexene-1,4-
A hexane solution of phenylbutene-1 and 7-methyl-1,6-octadiene was added in the polymerization vessel at a concentration of hexene-1 of 132 g /
Liter, 4-phenylbutene-1 concentration 39g / liter,
2.1 liters / hour so that the concentration of 7-methyl-1,6-octadiene was 10 g / liter, and a hexane slurry solution of a solid titanium catalyst component [a] as a catalyst had a titanium concentration of 0.04 mmol in the polymerization vessel. / l, so that 0.
4 liters, hexane solution of triisobutylaluminum so that the aluminum concentration in the polymerization vessel is 4 mmol / l, 1 liter / hour, hexane solution of trimethylmethoxysilane has a silane concentration of 1.3 mmol / l in the polymerization vessel It was continuously fed into each of the polymerization vessels at a rate of 0.5 liter per hour so that the amount became 1. On the other hand, the polymerization solution in the polymerization vessel was continuously withdrawn from the lower portion of the polymerization vessel so as to always have a volume of 2 liters. Further, from the upper part of the polymerization vessel, hydrogen was supplied at 0.8 liters per hour and nitrogen was supplied at 50 liters per hour.
The copolymerization reaction was carried out at 50 ° C. by circulating warm water in a jacket attached outside the polymerization vessel.

Next, a small amount of methanol was added to the polymerization solution extracted from the lower part of the polymerization vessel to stop the copolymerization reaction, and this polymerization solution was poured into a large amount of methanol to precipitate the copolymer. The copolymer was thoroughly washed with methanol, and then dried under reduced pressure at 130 ° C for 24 hours to obtain hexene-1,4-phenylbutene-1,7-methyl-1,6-octadiene copolymer at a rate of 122 g / hr. It was

With hexene-1 which constitutes the obtained copolymer
The molar ratio with 4-phenylbutene-1 (hexene-1 / 4-phenylbutene-1) is 75/25, and the iodine value is 9.4.
Met. The intrinsic viscosity [η] measured in decalin at 135 ° C was 5.7 dl / g. The above polymerization conditions are shown in Table 1.

[0098]

[Table 1]

(Production of Vulcanized Rubber) The higher α-olefin copolymer rubber produced by the above method (copolymer 1-a, 1
-b, 1-c) were blended according to Table 2, kneaded with an 8-inch open roll, and vulcanized at 150 ° C for 20 minutes, and the physical properties of the obtained vulcanizate were measured.

In the table, all parts by weight of the rubber composition were parts by weight, and the rubber properties were evaluated by the following test methods. That is, the strength characteristics are based on the tensile strength (T _B ), the wear resistance is based on the Lambourn method, and the braking performance (wet skid) on a wet road surface is 0 by the spectrometer.
It was evaluated by tan δ at 0 ° C. and rolling resistance was evaluated by tan δ at 50 ° C. by a spectrometer. Test method (1) The tensile test was performed according to JIS K 6301. That is, in the tensile test, tensile strength (T _B), was measured elongation (E _B). (2) In the bending test, the resistance to crack growth was examined with a DeMatcher tester according to JIS K6301. That is, the number of times of bending until the crack became 15 mm was measured. (3) The ozone resistance test (weather resistance test) is JIS K
6301 was measured. That is, J with a thickness of 3 mm
Using IS No. 1 dumbbell, deformation of 25% was given at a frequency of 100 rpm for 48 hours in an ozone chamber having an ozone concentration of 50 pphm, and the number of occurrences of ozone cracks was shown.

The number of ozone cracks is A (decimal), B
It is represented by (majority) and C (innumerable), and the higher the resistance from A to B and C, the worse the ozone resistance. (4) The adhesive property was shown in a peeling state by co-crosslinking a part of each surface of the test piece for bonding one side and the test piece to be bonded the other side. The sample is a strip test piece having a width of 1 inch.

The peeling condition is C for interfacial peeling and D for substrate breakage.
The adhesive strength of D is stronger than that of C.

[0103]

[Table 2]

[0104]

[Table 3]

1) RSS # 3 2) Nihon Synthetic Rubber Co., Ltd .: Nipol 1220 3) Mitsui Petrochemical Co., Ltd .: Mitsui EPT3045 4) Asahi Carbon Co., Ltd .: FEF # 605 5) N-oxydiethylene -2-benzothiazyl sulfenamide

[Brief description of drawings]

FIG. 1 is a flow chart showing the steps for preparing an olefin polymerization catalyst used in the production of the higher α-olefin copolymer rubber used in the present invention.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masaaki Kawasaki Aki 6-1-2, Waki, Waki-cho, Kuga-gun, Yamaguchi Mitsui Petrochemical Industry Co., Ltd.

Claims (4)

[Claims] 1. [I] A higher α-olefin having 6 to 20 carbon atoms, an aromatic ring-containing vinyl monomer represented by the following general formula (i), and a non-conjugated diene represented by the following general formula (ii). Higher α-olefin copolymer rubber and [II] diene rubber, and higher α-
Olefin copolymer rubber [I] and diene rubber [II]
And the weight ratio [[I] / [II]] is 5/95 to 50/50
A rubber composition for a tire sidewall, characterized in that: (In the formula, n is an integer of 0 to 5, and R ¹ , R ² and R ³
Are each independently a hydrogen atom or a carbon atom number of 1 to 8.
Represents an alkyl group of), (In the formula, n is an integer of 1 to 5 and R ⁴ is 1 carbon atom.
~ 4 alkyl groups, R ⁵ and R ⁶ represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and R ⁵ and R ⁶ are not both hydrogen atoms). 2. The intrinsic viscosity [η] of the higher α-olefin copolymer rubber [I] measured in a decalin solvent at 135 ° C. is in the range of 1.0 to 10.0 dl / g. The rubber composition for tire sidewalls according to claim 1. 3. The rubber composition for a tire sidewall according to claim 1, wherein the higher α-olefin copolymer rubber [I] has an iodine value of 1 to 50. 4. The rubber composition for a tire sidewall according to claim 1, wherein the diene rubber [II] is natural rubber, isoprene rubber, SBR, BR or a mixture thereof. object.