JP3183550B2 - Rubber composition for tire sidewall - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber composition for a tire sidewall excellent in strength properties, weather resistance, ozone resistance, dynamic fatigue resistance (bending fatigue resistance) and adhesiveness.

[0002]

BACKGROUND OF THE INVENTION It is said that the role of a sidewall portion in a pneumatic tire is to protect a carcass portion and relieve stress or strain in a tread portion during tire running. Therefore, the characteristics of the sidewall portion required for protection of the carcass portion include weather resistance with respect to ozone degradation, trauma resistance when traveling on a rough road, and adhesion to the carcass portion with respect to the side portion separation problem. On the other hand, the characteristics of the sidewall portion required for stress and strain relaxation of the tread portion include dynamic fatigue resistance,
Bending resistance. That is, the pneumatic tire is
Since it is used under various environments and conditions, various characteristics as described above are required. Moreover, recently, as road maintenance progresses and radial tires become more widespread, tire life is further extended, and among the above-mentioned characteristics, demands for improvement particularly in terms of dynamic fatigue resistance and weather resistance are increasing.

In general, as a method for improving the dynamic fatigue resistance of rubber, the effective use of butadiene rubber (BR) is mentioned as a typical example, and the blending of syndiotactic-1,2-polybutadiene short fibers has been proposed. (Special Publication 57-4
No. 530). However, syndiotactic-
Since rubber containing 1,2-polybutadiene short fiber is still insufficient in terms of weather resistance, an amine-based antioxidant and a paraffin-based wax are usually used in combination. Amine-based antiaging agents are typical antiozoning antioxidants, and paraffin wax has a function of forming a protective film on the surface of rubber to prevent attacks of ozone in the outside air. The agent is consumed due to migration during vulcanization of rubber, scattering during running of tires, and the like. Therefore,
In order to cope with the long life of today's tires, a large amount of the above-described anti-ozonant and wax is required, but these large amounts conversely lead to a decrease in dynamic fatigue resistance. There is a limit on the amount. Moreover, even if the antioxidant and wax are optimized for such general-purpose polymer rubber, the weather resistance and dynamic fatigue resistance of the grade currently required for tire sidewalls cannot be completely satisfied.

Therefore, as an approach from the viewpoint of a novel compounding technique, use of an ethylene-propylene copolymer rubber having good ozone resistance can be considered. However, this ethylene-propylene copolymer rubber has a problem in co-vulcanization with a diene rubber, and is not preferable because a separation problem occurs due to poor adhesion to carcass rubber. For example, U.S. Pat. No. 4,645,793 discloses the use of an ethylene / α-olefin copolymer rubber having improved weather resistance and ozone resistance. However, although this ethylene / α-olefin copolymer rubber has improved weather resistance and ozone resistance, it has problems such as reduced dynamic fatigue resistance and insufficient adhesion to carcass rubber. .

[0005] The inventors of the present invention have excellent weather resistance, ozone resistance and dynamic fatigue resistance (bending fatigue resistance).
In order to obtain a rubber composition for a tire sidewall excellent in adhesion (separation resistance), a keen research was conducted, and in the presence of a specific olefin polymerization catalyst, a specific higher α-olefin, a specific α, ω-diene and When a composition comprising a higher α-olefin copolymer rubber obtained by copolymerizing a specific non-conjugated diene and a diene rubber was used for a tire sidewall, this rubber composition was particularly excellent in the above properties. As a result, the present invention was found to be optimal as a rubber composition for a tire sidewall, and the present invention was completed.

[0006]

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

[0007]

SUMMARY OF THE INVENTION A rubber composition for a tire sidewall according to the present invention comprises a higher α-olefin having 6 to 20 carbon atoms, an α, ω-diene represented by the following general formula [I], and a following general formula: A higher α-olefin copolymer rubber (1) comprising a non-conjugated diene represented by the formula [II] and a diene rubber (2), wherein the higher α-olefin copolymer rubber (1) And the weight ratio of the diene rubber (2) to [(1) / (2)] is 5/95 to 50/50,
It is characterized by having excellent adhesion to scrap rubber .

[0008]

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In the formula [I], n is an integer of 1 to 3;
¹ and R ² each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.

[0010]

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In the formula [II], n is an integer of 1 to 5,
R ³ represents an alkyl group having 1 to 4 carbon atoms, R ⁴ and R ⁵ represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, and both R ⁴ and R ⁵ are hydrogen atoms. Absent.

[0012]

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 specific higher α-olefin copolymer rubber (1) and a specific diene rubber (2). Higher α-olefin copolymer rubber (1) The higher α-olefin copolymer rubber (1) used in the present invention comprises a specific higher α-olefin and a specific α, ω
A specific copolymer in which a diene and a specific non-conjugated diene are present in a specific ratio.

The higher α-olefin used in the present invention is a higher α-olefin having 6 to 20 carbon atoms,
Specifically, 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-methyldecene 1,
11-methyldodecene-1, 12-ethyltetradecene-1 and the like.

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

Α, ω-Diene The α, ω-diene used in the present invention is represented by the following general formula [I].

[0017]

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In the above general formula [I], n is 1 to 3
Wherein R ¹ and R ² each independently represent a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.
As the α, ω-diene as described above, specifically,
1,4-pentadiene, 1,5-hexadiene, 1,6
Heptadiene, 3-methyl-1,4-pentadiene,
3-methyl-1,5-hexadiene, 3-methyl-1,
6-heptadiene, 4-methyl-1,6-heptadiene, 3,3-dimethyl-1,4-pentadiene, 3,4
-Dimethyl-1,5-hexadiene, 4,4-dimethyl-1,6-heptadiene, 4-ethyl-1,6-heptadiene and the like.

In the above-mentioned higher α-olefin copolymer rubber, when R ¹ and R ² are hydrogen atoms, the above-mentioned repeating unit derived from α, ω-diene usually has the following structure. Formula [III] and / or Formula [I
V].

[0020]

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[0021]

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In the above-mentioned higher α-olefin copolymer rubber, each of the above-mentioned repeating units forms a substantially linear structure in which they are randomly arranged. The structure of each of these repeating units can be confirmed by ¹³ C-NMR. here,
A substantially linear structure means that a branched structure may be formed, but does not include a network crosslinked structure. The fact that the higher α-olefin copolymer rubber used in the present invention forms a substantially linear structure means that this copolymer rubber is completely dissolved in decalin at 135 ° C. This can be confirmed by not containing a polymer.

Non-conjugated diene The non-conjugated diene used in the present invention has the following general formula [I
I].

[0024]

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In the above general formula [II], n is an integer of 1 to 5, R ³ is an alkyl group having 1 to 4 carbon atoms, and R ⁴ and R ⁵ are a hydrogen atom or a carbon atom. 1 to
And R ⁴ and R ⁵ are not both hydrogen atoms.

Specific examples of the non-conjugated diene as described above include 4-methyl-1,4-hexadiene, 5-methyl-1,4-hexadiene, 4-ethyl-1,4-hexadiene, 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-
Examples thereof include 1,8-decadiene and 9-methyl-1,8-undecadiene.

In the present invention, the above non-conjugated dienes may be used alone or as a mixture of two or more. Further, in addition to the non-conjugated diene 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 constituent units derived from higher α-olefin and the constituent units derived from α, ω-diene (higher α-olefin / α, ω-diene) is 5
0/50 to 95/5, preferably 60/40 to 90/1
0, more preferably in the range of 65/35 to 90/10. The value of the molar ratio is a value obtained by measurement by ¹³ C-NMR method.

In the present invention, α, ω is added to the higher α-olefin.
-The processability of the higher α-olefin copolymer rubber can be improved by copolymerizing a diene. The content of the non-conjugated diene constituting the higher α-olefin copolymer rubber used in the present invention is 0.01 to 30 mol%, preferably 0.1 to 20 mol%, particularly preferably 0.1 to 20 mol%. It is in the range of 10 mol%. This characteristic value is a standard value when vulcanizing the higher α-olefin copolymer rubber used in the present invention with sulfur or peroxide.

The intrinsic viscosity [η] of the higher α-olefin copolymer rubber (1) used in the present invention measured in a decalin solvent at 135 ° C. is 1.0 to 10.0 dl / g, preferably 1. It is in the range of 5-7 dl / g. This characteristic value is a scale indicating the molecular weight of the higher α-olefin copolymer rubber used in the present invention.If the molecular weight is in the above range, the strength characteristics, weather resistance, ozone resistance, heat aging. A copolymer excellent in properties such as properties, low-temperature properties, and dynamic fatigue resistance can be obtained.

The higher α- used in the present invention as described above
The olefin copolymer rubber (1) can be produced by the following method. The higher α-olefin copolymer rubber (1) used in the present invention is represented by the above general formula [I] and a higher α-olefin having 6 to 20 carbon atoms in the presence of an olefin polymerization catalyst. α, ω-diene,
It is obtained by copolymerizing with the non-conjugated diene represented by the general formula [II].

The olefin polymerization catalyst used in the present invention comprises 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 flowchart of a method for preparing a catalyst component for olefin polymerization 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 comprises:
It is a highly active catalyst component containing magnesium, titanium, halogen and an electron donor as essential components.

The 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, the titanium compound used for preparing the solid titanium catalyst component (a) includes, for example, 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 exemplified.

More specifically, TiCl_Four, TiB
r_Four, TiI_Four Titanium tetrahalide such as Ti;
(OCH_Three) Cl_Three, Ti (OC_TwoH_Five) Cl_Three, Ti (O
-n-C_FourH₉) Cl_Three, Ti (OC_TwoH_Five) Br_Three, Ti (O
-iso-C_FourH₉) Br_Three Trihalogenated alkoxy such as
Titanium; Ti (OCH_Three)_TwoCl_Two, Ti (OC_TwoH_Five)_TwoC
l_Two, Ti (On-C_FourH₉)_TwoCl _Two, Ti (OC_TwoH_Five)_Two
Br_TwoDialkoxytitanium dihalide such as Ti; Ti
(OCH_Three)_ThreeCl, Ti (OC_TwoH_Five)_ThreeCl, Ti (O
-n-C_FourH₉)_ThreeCl, Ti (OC_TwoH_Five)_ThreeMo such as Br
No halogenated trialkoxy titanium; Ti (OC
H_Three)_Four, Ti (OC_TwoH_Five)_Four, Ti (On-C_FourH₉)_Four,
Ti (O-iso-C_FourH₉)_Four, Ti (O-2-ethylhexyl)
Le)_Four Such as tetraalkoxy titanium
Can be.

Of these, halogen-containing titanium compounds, particularly titanium tetrahalide, are preferred. Among them,
Titanium tetrachloride is particularly preferably used. These titanium compounds may be used alone or in combination of two or more. In addition, these titanium compounds
It may be diluted with a hydrocarbon compound or a halogenated hydrocarbon compound.

In the present invention, a trivalent titanium compound,
A tetravalent titanium compound is used, and a tetravalent titanium compound is particularly preferable. 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.

Here, examples of the magnesium compound having a reducing property include a magnesium compound having a magnesium-carbon bond or a magnesium-hydrogen bond. Specific examples of the magnesium compound having such a reducing property include dimethylmagnesium, diethylmagnesium, dipropylmagnesium, dibutylmagnesium, diamylmagnesium, dihexylmagnesium, didecylmagnesium, ethylmagnesium chloride, propylmagnesiumchloride, 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 organic aluminum compound described later. These magnesium compounds may be liquid or solid.

Specific examples of the non-reducing magnesium compound include magnesium halides such as magnesium chloride, magnesium bromide, magnesium iodide and magnesium fluoride; methoxy magnesium chloride, ethoxy magnesium chloride, and isopropoxy magnesium chloride. Alkoxymagnesium halides such as magnesium, butoxymagnesium chloride and octoxymagnesium chloride; alkoxymagnesium halides such as phenoxymagnesium chloride and methylphenoxymagnesium chloride; ethoxymagnesium, isopropoxymagnesium, butoxymagnesium, n-octoxymagnesium, 2-ethylhexoxymagnesium Alkoxymagnesium such as;
Alloxymagineium such as phenoxymagnesium and dimethylphenoxymagnesium; and magnesium carboxylate 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 the preparation of the catalyst component. In order to derive a non-reducing magnesium compound from a reducing magnesium compound, for example, a reducing magnesium compound is converted to a polysiloxane compound, a halogen-containing silane compound, a halogen-containing aluminum compound, an ester, an alcohol, or the like. What is necessary is just to contact with a compound.

In the present invention, in addition to the above-mentioned magnesium compound having a reducing property and the magnesium compound having no reducing property, the magnesium compound may be a complex compound, a double compound or another compound of the above-mentioned magnesium compound and another metal. It may be a mixture with a metal compound. Further, a mixture of two or more of the above compounds may be used.

In the present invention, among these, magnesium compounds having no reducing property are preferred, and halogen-containing magnesium compounds are particularly preferred. Of these, magnesium chloride, alkoxymagnesium chloride and allyloxymagnesium chloride are preferably used. Can be

In the present invention, examples of the electron donor used for preparing the solid titanium catalyst component (a) include an organic carboxylic acid ester and a polyvalent carboxylic acid ester described below. Compounds having the following skeleton.

[0044]

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[0045]

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[0046]

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[0047]

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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.
Preferably, at least one of R ³ and R ⁴ is a substituted or unsubstituted hydrocarbon group. R ³ and R ⁴ may be connected to each other to form a cyclic structure. Examples of the substituted hydrocarbon group include a substituted hydrocarbon group containing a different atom such as N, O, and S. For example, -C-O-C
-, - COOR, -COOH, -OH , -SO 3 H, -
Substituted hydrocarbon groups having a structure such as C—N—C— and —NH ₂ are mentioned.

Among 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, α-
Diisobutyl methyl glutarate, dibutyl methyl malonate, diethyl malonate, diethyl ethyl malonate, diethyl isopropyl malonate, diethyl butyl malonate,
Diethyl phenylmalonate, diethyl diethylmalonate, diethyl allylmalonate, diethyldiisobutylmalonate, diethyldinormalbutylmalonate, dimethylmaleate, monooctylmaleate, diisooctylmaleate, diisobutylmaleate, diisobutylbutylmaleate, butylmaleate Fatty acid polycarboxylic acid esters such as diethyl acrylate, diisopropyl β-methylglutarate, diallyl ethylsuccinate, di-2-ethylhexyl fumarate, diethyl itaconate, diisobutyl itaconate, diisooctyl citrate, and dimethyl citrate; 1,2-cyclohexane Aliphatic polycarbonates such as diethyl carboxylate, diisobutyl 1,2-cyclohexanecarboxylate, diethyl tetrahydrophthalate, diethyl nadicate Rubonates; monoethyl phthalate, dimethyl phthalate, methyl ethyl phthalate,
Monoisobutyl phthalate, diethyl phthalate, ethyl isobutyl phthalate, mono-normal butyl phthalate, ethyl normal butyl phthalate, di-n-propyl phthalate,
Diisopropyl phthalate, di-n-butyl phthalate, diisobutyl phthalate, di-n-heptyl phthalate, di-2-ethylhexyl phthalate, didecyl phthalate, benzyl butyl phthalate, diphenyl phthalate, diethyl naphthalene dicarboxylate, Aromatic polycarboxylic esters such as dibutyl naphthalene dicarboxylate, triethyl trimellitate and 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. And esters derived from long-chain dicarboxylic acids.

Among these polycarboxylic acid esters,
Compounds having a skeleton represented by the aforementioned general formula are preferable, and more preferably esters derived from phthalic acid, maleic acid, substituted malonic acid and the like and alcohols having 2 or more carbon atoms, and phthalic acid and carbon atoms Number 2
Diesters obtained by the above reaction with alcohols are particularly preferred.

As these polycarboxylic acid esters, it is not always necessary to use the above-mentioned polycarboxylic acid esters as starting materials, and these polycarboxylic acid esters may be used during the preparation of the solid titanium catalyst component (a). A polycarboxylic acid ester may be formed in the step of preparing the solid titanium catalyst component (a) using a compound capable of deriving an ester.

In the present invention, examples of the electron donor other than the polyvalent carboxylic acid which can be used in preparing the solid titanium catalyst component (a) include alcohols, amines, amides, and the like as described below. Ethers, ketones, nitriles, phosphines, stippins, arsines, phosphoramides, esters, thioethers,
Organosilicon compounds such as thioesters, acid anhydrides, acid halides, aldehydes, alcoholates, 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) into contact with an electron donor and a titanium compound. In order to produce the solid titanium catalyst component (a), a known method for preparing a highly active titanium catalyst component from a magnesium compound, a titanium compound, and an electron donor can be employed. The above components may be brought into contact with each other in the presence of another reaction reagent such as silicon, phosphorus, and aluminum.

The method for producing the solid titanium catalyst component (a) will be briefly described below with several examples. (1) A method in which a magnesium compound or a complex compound comprising a magnesium compound and an electron donor is reacted with a titanium compound in a liquid phase. This reaction may be performed in the presence of a grinding aid or the like. Further, when reacting as described above, the solid compound may be pulverized. Furthermore, when reacting as described above, each component may be pretreated with an electron donor and / or a reaction assistant such as an organoaluminum compound or a halogen-containing silicon compound. In this method, the electron donor is used at least once. (2) a liquid magnesium compound having no reducing property;
A method in which a liquid titanium compound is reacted in the presence of an electron donor to precipitate a solid titanium composite agent. (3) A method in which a titanium compound is further reacted with the reaction product obtained in (2). (4) The reaction product obtained in (1) or (2)
A method in which an electron donor and a titanium compound are further reacted. (5) A solid obtained by pulverizing a magnesium compound or a complex compound comprising a magnesium compound and an electron donor in the presence of a titanium compound is treated with any of a halogen, a halogen compound and an aromatic hydrocarbon. Method. In this method, a magnesium compound or a complex compound comprising a magnesium compound and an electron donor may be ground in the presence of a grinding aid or the like. Alternatively, a magnesium compound or a complex compound composed of a magnesium compound and an electron donor may be ground in the presence of a titanium compound, pre-treated with a reaction aid, and then treated with a halogen or the like. In addition, examples of the reaction assistant include an organic aluminum compound and a halogen-containing silicon compound. In this method, an electron donor is used at least once. (6) A method of treating the compound obtained in the above (1) to (4) with a halogen, a halogen compound or an aromatic hydrocarbon. (7) A method of contacting a reaction product of a metal acid compound, dihydrocarbylmagnesium and a halogen-containing alcohol with an electron donor and a titanium compound. (8) A method in which a magnesium compound such as a magnesium salt of an organic acid, alkoxymagnesium, or aryloxymagnesium is reacted 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 the above (1) to (8), a method using a liquid titanium halide at the time of preparing the catalyst, a method using a titanium compound, or a method using When using a compound, a method using a halogenated hydrocarbon is preferred.

The amount of each of the above 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 the electron donor is about 0.01-5
Moles, preferably 0.05 to 2 moles, and about 0.01 to 500 moles, preferably 0.05 to 3 moles, of the titanium compound.
It is used in an amount of 00 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 to 10,
Preferably, 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 small crystal size as compared with a commercially available magnesium halide, and usually has a specific surface area of about 50 m ² / g or more, preferably about 60 to 1, 000m
² / g, more preferably about 100 to 800 m ² / g. Since the solid titanium catalyst component (a) forms a catalyst component by integrating the above components, the composition is not substantially changed by hexane washing.

Such a solid titanium catalyst component (a) is
Although it can be used alone, it can also be used after being diluted with an inorganic or organic compound such as a silicon compound, an aluminum compound, or a polyolefin. In addition, when a diluent is used, even if it is smaller than the above-mentioned specific surface area, it shows high catalytic activity.

A method for preparing such a highly active titanium catalyst component is described in, for example, JP-A-50-108385.
No. 50-126590, No. 51-20297, No. 51-28189, No. 51-64586, No. 51-92885, No. 51-1366
No. 25, No. 52-87489, No. 52-100596,
No. 52-147688, No. 52-104593, No. 53-2580, No. 53-40093, No. 53-40094, No. 53-430
No. 94, No. 55-135102, No. 55-135103,
No. 55-152710, No. 56-811, No. 56-11908, No. 56-18606, No. 58-83006, No. 58-1387
No. 05, No. 58-138706, No. 58-138707,
No. 58-138708, No. 58-138709, No. 58-1387
No. 10, No. 58-138715, No. 60-23404, No.
These are disclosed in JP-A-61-21109, JP-A-61-37802, and JP-A-61-37803.

As the organoaluminum compound catalyst component (b) used in the present invention, a compound having at least one Al-carbon bond in the molecule can be used. Examples of such a compound include: (i) a compound represented by the general formula (R ¹ ) _m Al (O (R ² )) _n H _p X _q (wherein R ¹ and R ² each usually have 1 to 15 carbon atoms) ,
Preferred are hydrocarbon groups containing 1 to 4 hydrocarbon groups, which may be the same or different. X represents a halogen atom, m is 0 <m ≦ 3, n is 0 ≦ n <3, and p is 0 ≦ p <
3, q is a number satisfying 0 ≦ q <3, and m +
(ii) an organoaluminum compound represented by the formula (M ¹ ) Al (R ¹ ) ₄ (wherein M ¹ is Li, Na, K, and R ¹ is the above-mentioned (i) And the same as R ¹ in formula ( ¹ ), and a complex alkylated product of a Group I metal and aluminum.

As the organoaluminum compound belonging to the above (i), the following compounds can be exemplified. Formula _{^{(R 1) n Al (O}} (R 2)) in _3-m (wherein, R ¹ R ¹ and R ² in the (i), R
Same as ² . m is a number preferably satisfying 1.5 ≦ m ≦ 3), the general formula ^{_{(R 1) m AlX 3-}} m ( wherein, R ¹ is the (i) the same .X is halogen and R ¹ in, m is a number preferably satisfying 0 <m <3), the general formula ^{_{(R 1) m AlH 3-}} m ( wherein, R ¹ is (i) above same .m preferably 2 ≦ a R ¹ in m <is a number satisfying 3), the general formula _{^{(R 1) m Al (oR}} 2) n X q ( wherein, R ¹ and R ² are the (i) R ¹ in, R
Same as ² . X is halogen, m is 0 <m ≦ 3, n is 0 ≦ n
<3, q is a number satisfying 0 ≦ q <3, and m + n + q
= 3).

As the aluminum compound belonging to the above (i), more specifically, trialkylaluminum such as triethylaluminum and tributylaluminum; trialkenylaluminum such as triisoprenylaluminum; diethylaluminum ethoxide, dibutylaluminum butoxide and the like Dialkylaluminum alkoxides; alkylaluminum sesquialkoxides such as ethylaluminum sesquiethoxide and butylaluminum sesquibutoxide; (R ¹ ) _2.5 A
l (O (R ²⁾⁾ partially alkoxylated alkyl aluminum having an average composition represented by like _0.5;
Dialkylaluminum halides such as diethylaluminum chloride, dibutylaluminum chloride and diethylaluminum bromide; alkylaluminum sesquihalides such as ethylaluminum sesquichloride, butylaluminum sesquichloride and ethylaluminum sesquibromide; ethylaluminum dichloride, propylaluminum dichloride and butylaluminum dibromide Alkyl aluminum dihalides such as alkylaluminum dihalide; dialkylaluminum hydrides such as diethylaluminum hydride and dibutylaluminum hydride; alkylaluminum dihydrides such as ethylaluminum dihydride and propylaluminum dihydride Partially hydrogenated Kill aluminum; ethylaluminum ethoxy chloride, butyl aluminum butoxide cycloalkyl chloride, can be mentioned partially alkoxylated and halogenated alkylaluminum such as ethylaluminum ethoxy bromide.

Examples of the compound similar to the aluminum compound belonging to the above (i) include an organic aluminum compound in which two or more aluminum atoms are bonded via an oxygen atom or a nitrogen atom. Such compounds include, for example, (C ₂ H ₅ ) ₂ AlOAl (C ₂ H ₅ ) ₂ ,
(C ₄ H ₉ ) ₂ AlOAl (C ₄ H ₉ ) ₂ , (C ₂ H ₅ ) ₂ Al
N (C ₂ H ₅ ) Al (C ₂ H ₅ ) ₂ and methylaminooxane.

Compounds belonging to the above (ii) include L
iAl (C ₂ H ₅ ) ₄ and LiAl (C ₇ H ₁₅ ) ₄ can be exemplified. Among these, it is particularly preferable to use a trialkyl aluminum or an alkyl aluminum to which two or more of the above-mentioned aluminum compounds are bonded.

Examples of the electron donor catalyst component (c) include alcohols, phenols, ketones, aldehydes, carboxylic acids, esters of organic or inorganic acids, ethers, acid amides, acid anhydrides, and oxygen-containing compounds such as alkoxysilanes. An electron donor, a nitrogen-containing electron donor such as ammonia, amine, nitrile, and isocyanate, or the above-mentioned polyvalent carboxylic acid ester 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, isopropyl benzyl alcohol, etc. Alcohols having 1 to 18 atoms; phenol, cresol, xylenol, ethylphenol, propylphenol,
C6-C20 which may have a lower alkyl group, such as nonylphenol, cumylphenol and naphthol.
Phenols; ketones having 3 to 15 carbon atoms such as acetone, methyl ethyl ketone, methyl isobutyl ketone, acetophenone, benzophenone and benzoquinone;
Aldehydes having 2 to 15 carbon atoms such as acetaldehyde, propionaldehyde, octylaldehyde, benzaldehyde, tolualdehyde, naphthaldehyde; methyl formate, methyl acetate, ethyl acetate, vinyl 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, methylmalo Diisobutyl, cyclohexene carboxylic di -n- hexyl, nadic diethyl, tetrahydrophthalic acid diisopropyl, diethyl phthalate, diethyl phthalate, diisobutyl phthalate, di -
Organic acid esters having 2 to 30 carbon atoms such as n-butyl, di-2-ethylhexyl phthalate, γ-butyrolactone, δ-valerolactone, coumarin, phthalide, ethylene carbonate; acetyl chloride, benzoyl chloride, toluic acid chloride, anise 2-1 carbon atoms such as acid chloride
5 acid halides; methyl ether, ethyl ether,
Ethers having 2 to 20 carbon atoms such as isopropyl ether, butyl ether, amyl ether, tetrahydrofuran, anisole and diphenyl ether; acid amides such as acetic acid amide, benzoic acid amide and toluic acid amide; methylamine, ethylamine, diethylamine and tributylamine Amines such as, for example, piperidine, tribenzylamine, aniline, pyridine, picoline, tetramethylenediamine; nitriles such as acetonitrile, benzonitrile, tolunitrile; acid anhydrides such as acetic anhydride, phthalic anhydride and benzoic anhydride; Can be

As the electron donor (c), an organosilicon compound represented by the following general formula [II] can also be used. R _n Si (OR ′) _4-n ... [1] (wherein R and R ′ are hydrocarbon groups, and n is 0 <n
<4. As the organosilicon compound represented by the general formula [1], specifically, trimethylmethoxysilane, trimethylethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane,
Diisopropyldimethoxysilane, t-butylmethyldimethoxysilane, t-butylmethyldiethoxysilane, t-amylmethyldiethoxysilane, diphenyldimethoxysilane, phenylmethyldimethoxysilane, diphenyldiethoxysilane, bis-ο-tolyldimethoxysilane,
Bis-m-tolyldimethoxysilane, bis-p-tolyldimethoxysilane, bis-p-tolyldiethoxysilane, bisethylphenyldimethoxysilane, dicyclohexyldimethoxysilane, cyclohexylmethyldimethoxysilane, cyclohexylmethyldiethoxysilane, ethyltrimethoxysilane , Ethyltriethoxysilane, vinyltrimethoxysilane, methyltrimethoxysilane, n
-Propyltriethoxysilane, decyltrimethoxysilane, decyltriethoxysilane, 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-norbornanemethyl Dimethoxysilane,
Ethyl silicate, butyl silicate, trimethylphenoxysilane, methyltriaryloxysilane, 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, and diphenyldiethoxysilane are preferred.

Further, as the electron donor catalyst component (c), an organosilicon compound represented by the following general formula [2] can be used. SiR ¹ R ² _m (OR ³ ) _3-m [2] (wherein R ¹ is a cyclopentyl group or a cyclopentyl group having an alkyl group, and R ² has an alkyl group, a cyclopentyl group and an alkyl group 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 Wherein R ¹ is a cyclopentyl group having an alkyl group such as a 2-methylcyclopentyl group, a 3-methylcyclopentyl group, a 2-ethylcyclopentyl group, a 2,3-dimethylcyclopentyl group in addition to the cyclopentyl group Can be mentioned.

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

In the above 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 the 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 and dicyclopentyldiethoxysilane; tricyclopentylmethoxysilane, tricyclopentylethoxysilane, Cyclopentylmethylmethoxysilane,
Monoallocoxysilanes such as dicyclopentylethylmethoxysilane, dicyclopentylmethylethoxysilane, cyclopentyldimethylmethoxysilane, cyclopentyldiethylmethoxysilane, cyclopentyldimethylethoxysilane and the like can be mentioned. 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), the organoaluminum compound catalyst component (b), and the electron donor catalyst component (c) as described above. In the present invention, a higher α-olefin and α,
The ω-diene and the non-conjugated diene are polymerized. After preliminarily polymerizing the α-olefin or higher α-olefin using the catalyst for olefin polymerization, the higher α-olefin and α, The ω-diene and the non-conjugated diene can be polymerized (main polymerization). During the prepolymerization, 0.1 to 500 per gram of the olefin polymerization catalyst is used.
g, preferably 0.3 to 300 g, particularly preferably 1 to
The α-olefin or higher α-olefin is prepolymerized in an amount of 100 g.

In the prepolymerization, a catalyst having a considerably 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 as follows:
Usually, about 0.01 to 200 mmol, preferably about 0.1 to 100 mmol, and particularly preferably 1 to 50 mmol, per liter of the inert hydrocarbon medium described below, in terms of titanium atoms.
Desirably, it is in the mmol range.

The amount of the organoaluminum catalyst component (b) is
0.1 to 500 g per 1 g of the solid titanium catalyst component (a),
The amount is preferably such that a polymer of 0.3 to 300 g is produced, and usually about 0.1 to 100 mol, preferably about 0.1 to 100 mol per mol of titanium atom in the solid titanium catalyst component (a). It is desirable that the amount is 5 to 50 mol, particularly preferably 1 to 20 mol.

The electron donor catalyst component (c) is used in an amount of 0.1 to 5 per mole 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 a higher α-olefin and the above catalyst component to an inert hydrocarbon medium. Specific examples of the inert hydrogen medium used at this time include aliphatic hydrocarbons such as propane, butane, pentane, hexane, heptane, octane, decane, dodecane, and kerosene; cyclopentane, cyclohexane, methylcyclopentane, and the like. Alicyclic hydrocarbons; aromatic hydrocarbons such as benzene, toluene, and xylene; halogenated hydrocarbons such as ethylene chloride and chlorobenzene; and mixtures thereof. Among these inert hydrocarbon media, it is particularly preferable to use an aliphatic hydrocarbon.
The olefin or higher α-olefin itself can be pre-polymerized in a solvent, or can be pre-polymerized 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 during the prepolymerization is usually about -20 to + 100 ° C, preferably about -2.
It is desirable to be in the range of 0 to + 80 ° C, more preferably 0 to + 40 ° C.

In the prepolymerization, a molecular weight regulator such as hydrogen may be used. Such a molecular weight modifier has an intrinsic viscosity [η] of about 0.1 of a polymer obtained by prepolymerization, measured in a decalin solvent at 135 ° C.
It is desirable to use an amount of 2 dl / g or more, preferably about 0.5 to 10 dl / g.

As described above, the prepolymerization is carried out so that about 0.1 to 500 g, preferably about 0.3 to 300 g, and particularly preferably 1 to 100 g of polymer is produced per 1 g of the solid titanium catalyst component (a). It is desirable to carry out. 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 ( c) in the presence of an olefin polymerization catalyst formed from
-Copolymerization (main polymerization) of olefin, α, ω-diene and non-conjugated diene.

In the case of the copolymerization (main polymerization) of a higher α-olefin, α, ω-diene and non-conjugated diene, an olefin polymerization catalyst is used as an organoaluminum compound catalyst component in addition to the olefin polymerization catalyst. The same components as the organoaluminum compound catalyst component (b) used in producing the catalyst for use can be used. In addition, in the copolymerization (main polymerization) of a higher α-olefin, α, ω-diene, and a non-conjugated diene, the electron donor catalyst component used for producing an olefin polymerization catalyst is used. Components similar to the donor catalyst component (c) can be used. The organoaluminum compound and the electron donor used in the copolymerization of the higher α-olefin, α, ω-diene and non-conjugated diene (main polymerization) are not necessarily prepared by preparing the above-mentioned olefin polymerization catalyst. It need not be the same as the organoaluminum compound and electron donor used in the reaction.

The copolymerization (main polymerization) of a higher α-olefin, α, ω-diene and non-conjugated diene is usually carried out in a liquid phase. As the reaction medium for the main polymerization, the above-mentioned inert hydrocarbon medium can be used, or an olefin liquid at the reaction temperature can be used.

In the copolymerization (main polymerization) of a higher α-olefin, α, ω-diene and non-conjugated diene, the solid titanium catalyst component (a) is converted into titanium atoms 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 organic aluminum catalyst component (b)
The metal atom in the organoaluminum compound catalyst component (b) is usually about 1 to 2,000 moles, preferably about 5 to 5 moles per mole of titanium atom in the solid titanium catalyst component (a).
It is used in an amount of 500 moles. Further, the electron donor catalyst component (c) is usually added in an amount of about 0.00 per mole of metal atom in the organoaluminum compound catalyst component (b).
It is used in an amount of 1 to 10 mol, preferably 0.01 to 2 mol, particularly preferably 0.05 to 1 mol.

When hydrogen is used at the time of the main polymerization, the molecular weight of the obtained polymer can be adjusted. In the present invention, the polymerization temperature of the higher α-olefin, α, ω-diene and non-conjugated diene is usually about 20 to 200 ° C, preferably about 40 to 100 ° C, and the pressure is usually normal pressure to normal pressure. 100
kg / cm ^2, preferably from normal pressure to 50 kg / cm ² . In the copolymerization (main polymerization) of a higher α-olefin, α, ω-diene and non-conjugated diene,
It can be carried out by any of batch, semi-continuous and continuous methods. Further, the polymerization can be carried out in two or more stages by changing the reaction conditions.

Diene Rubber (2) The diene rubber (2) used in the present invention is a conventionally known diene rubber, specifically, natural rubber, isoprene rubber, SBR, BR, CR, NBR, etc. Is mentioned.

As the natural rubber, natural rubber standardized by the Green Book (international quality packaging standard for various grades of natural rubber) is generally used. Further, as the isoprene rubber, an isoprene rubber having a specific gravity of 0.91 to 0.94 and a Mooney viscosity [ML _{1 + 4} (100 ° C.)] of 30 to 120 is generally used. 0.91 to 0.98, and a Mooney viscosity [ML _{1 + 4}
(100 ° C.)] of 20 to 120 is generally used.

Further, BR has a specific gravity of 0.90 to
0.95 and Mooney viscosity [ML _{1 + 4} (100
° C)] is 20 to 120.
In the present invention, the diene rubber as described above is used alone.
May be used, or may be used as a mixture of two or more kinds.
No.

Of the diene rubbers, natural rubber, isoprene rubber, SBR, BR or a mixture thereof is preferably used. Compounding ratio The compounding ratio of the higher α-olefin copolymer rubber (1) and the diene rubber (2) constituting the rubber composition for a tire sidewall according to the present invention is the weight ratio [(1) /
(2)] from 5/95 to 50/50, preferably 10/9
0/40/60, more preferably 10 / 90-30 /
70.

The rubber composition for a tire sidewall according to the present invention can be produced by employing a known rubbery polymer mixing method such as a mixing method using a mixer such as a Banbury mixer. In the present invention, a usual rubber compounding agent is used at the time of compounding the rubber. Examples of such compounding agents include rubber reinforcing agents such as carbon black and finely divided silica; softening agents; fillers such as light calcium carbonate, heavy calcium carbonate, talc, clay and silica; tackifiers; waxes; Resins; zinc oxide; antioxidants; antiozonants; processing aids and vulcanizing activators. These compounding agents can be used alone or in combination of two or more.

The vulcanizing activator is generally preferably added at the second stage of the formulation, which may be a Banbury mixer usually operated at a temperature not exceeding about 60 ° C. The vulcanization activator may be sulfur or sulfur containing various accelerators.

The vulcanizate of the rubber composition for a tire sidewall according to the present invention is a compound comprising the above-mentioned higher α-olefin copolymer rubber (1), diene rubber (2) and a compounding agent. At a temperature of 150 to 200 ° C. for 5 to 60
It can be obtained by adopting a usual vulcanization method of heating for a minute and vulcanizing.

[0096]

The rubber composition for a tire sidewall according to the present invention contains a specific higher α-olefin copolymer rubber (1) and a specific diene rubber (2) in a specific ratio. Therefore, in addition to having excellent strength properties, weather resistance, ozone resistance, and dynamic fatigue resistance (bending fatigue resistance), there is an effect that adhesiveness (separation resistance) is excellent.
A vulcanizate having such an effect can be provided.

Hereinafter, the present invention will be described with reference to Examples.
The present invention is not limited to these examples. The methods for measuring physical properties adopted in the examples and the like are described below. (1) The tensile test was measured according to JIS K6301. That is, in the tensile test, the tensile strength (T _B ) and the elongation (E _B ) were measured. (2) In the bending test, resistance to crack growth was examined using 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 based on JIS K
Measured according to 6301. That is, J of 3 mm in thickness
Using an IS No. 1 dumbbell, a deformation of 25% was given at a frequency of 100 rpm for 48 hours in an ozone chamber with an ozone concentration of 50 pphm, and the occurrence of ozone cracks was indicated by a number.

The number of generated ozone cracks is A (decimal), B
It is represented by (many) and C (innumerable), and from A to B and C, the poorer the ozone resistance is. (4) Adhesion properties were shown in a peeled state by co-cross-linking one part of each surface of the test piece for adhesion and the other part of the test piece to be bonded. The sample is a 1-inch wide strip test piece.

The peeling conditions were as follows: C for interface peeling and D for substrate destruction.
, And indicates that D has a stronger adhesive force than C. Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited to these examples.

[0100]

Examples 1 to 5 and Comparative Examples 1 to 4 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 that, 21.3 g of phthalic anhydride was added to the solution, and the mixture was further stirred and mixed at 130 ° C. for 1 hour to dissolve phthalic anhydride in the homogeneous solution. After cooling the homogeneous solution thus obtained to room temperature, 75 ml of titanium tetrachloride 2 was kept at -20 ° C.
The entire amount was dropped into 00 ml over 1 hour. After completion of the charging, the temperature of the mixed solution was raised to 110 ° C. over 4 hours. When the temperature reached 110 ° C., 5.22 g of diisobutyl phthalate was added, and the mixture was kept under stirring at the same temperature for 2 hours. After completion of the reaction for 2 hours, a solid portion was collected by hot filtration, and the solid portion was resuspended in 275 ml of titanium tetrachloride, and then heated again at 110 ° C. for 2 hours. After the completion of the reaction, the solid portion was collected by hot filtration again,
The plate was washed sufficiently with decane and hexane at 10 ° C. until no free titanium compound was detected in the washing solution. 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 solid titanium catalyst component (a) thus obtained was composed of 2.5% by weight of titanium,
5% by weight, 19% by weight of magnesium and 13.5% by weight of diisobutyl phthalate. [Polymerization] The copolymerization reaction of octene-1, 1,5-hexadiene and 7-methyl-1,6-octadiene was continuously performed using a 4-liter glass polymerization vessel equipped with stirring blades. Was.

That is, octene-1,
A hexane solution of 1,5-hexadiene and 7-methyl-1,6-octadiene was used to prepare an octene-1 concentration of 200 g / liter and a 1,5-hexadiene concentration of 3 in a polymerization vessel.
A hexane slurry solution of the solid titanium catalyst component (a) was used as a catalyst at a rate of 2.1 g / h so that the concentration of 9 g / l and 7-methyl-1,6-octadiene became 10 g / l. Of hexane solution of triisobutylaluminum at a rate of 0.045 mmol / l and 1 liter of a trimethylmethoxysilane at a rate of 1 liter / hour such that the aluminum concentration in the polymerization vessel is 8 mmol / l. A hexane solution having a silane concentration of 2.6 mmol /
Liters were continuously fed into the polymerization reactor at a rate of 0.5 liter per hour. On the other hand, the polymerization solution in the polymerization vessel was continuously drained from the lower part of the polymerization vessel so that the polymerization solution was always 2 liters. From the top of the polymerization vessel, hydrogen was supplied at 1 liter / hour and nitrogen was supplied at 50 liter / hour. The copolymerization reaction was carried out at 50 ° C. by circulating warm water through a jacket attached outside the polymerization vessel.

Next, a small amount of methanol was added to the polymerization solution taken out 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 a copolymer. After sufficiently washing the copolymer with methanol, it was dried under reduced pressure at 140 ° C. for 24 hours to give octene-1.
A 1,5-hexadiene / 7-methyl-1,6-octadiene copolymer was obtained at a rate of 90 g / h.

Octene-1 constituting the obtained copolymer
And the molar ratio of 1,5-hexadiene (octene-1 /
(1,5-hexadiene) was 68/32, and the 7-methyl-1,6-octadiene content was 3.1 mol%. The intrinsic viscosity [η] of the copolymer measured in decalin at 135 ° C. was 4.8 dl / g.

The above polymerization conditions are shown in Table 1.

[0105]

[Table 1]

(Production of vulcanized rubber) The higher α-olefin copolymer rubber [copolymer (1-
a), (1-b) and (1-c)] were blended according to Table 2, kneaded with an 8-inch open roll, and heated at 150 ° C.
For 20 minutes, and the physical properties of the obtained vulcanized product were measured.

Table 2 shows the results. The unit of the numerical values in the rubber compounding ratio in Table 2 is parts by weight.

[0108]

[Table 2]

[0109]

[Table 3]

[Brief description of the drawings]

FIG. 1 is a flowchart showing a process for preparing an olefin polymerization catalyst used in producing a higher α-olefin copolymer rubber used in the present invention.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masaaki Kawasaki 1-2-1, Waki, Waki-machi, Kuga-gun, Yamaguchi Prefecture Inside Mitsui Petrochemical Industry Co., Ltd. (72) Inventor Toshimasa Takada Kuga-gun, Yamaguchi Prefecture 6-1-2, Waki, Wakicho Mitsui Petrochemical Industries, Ltd. (56) References JP-A-5-247283 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 9/00 B60C 1/00 B60C 13/00 C08L 23/20

Claims (4)

(57) [Claims] 1. A higher α-olefin comprising a higher α-olefin having 6 to 20 carbon atoms, an α, ω-diene represented by the following general formula [I], and a non-conjugated diene represented by the following general formula [II]: -An olefin copolymer rubber (1) and a diene rubber (2), and the weight ratio of the higher α-olefin copolymer rubber (1) and the diene rubber (2) is [ (1) / (2)] 5 / 95-
50/50, excellent adhesion to carcass rubber
A rubber composition for a tire sidewall, characterized in that that; ## STR1 ## Wherein n is an integer of 1 to 3, and R ¹ and R ² are
Each independently represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms], [In the formula, n is an integer of 1 to 5, and R ³ has 1 carbon atom.
Represents to 4 alkyl groups, R ⁴ and R ⁵ represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms, R ⁴
And R ⁵ cannot both be hydrogen atoms]. 2. The method according to claim 1, wherein the intrinsic viscosity [η] of the higher α-olefin copolymer rubber (1) measured in a decalin solvent at 135 ° C. is in the range of 1.0 to 10.0 dl / g. The rubber composition for a tire sidewall according to claim 1, wherein: 3. The non-conjugated diene [II] content of the higher α-olefin copolymer rubber (1) is 0.01 to 30.
The rubber composition for a tire sidewall according to claim 1 or 2, which is mol%. 4. The rubber composition for a tire sidewall according to claim 1, wherein the diene rubber (2) is natural rubber, isoprene rubber, SBR, BR or a mixture thereof. object.