JP2003082174A - Rubber composition and its use - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a rubber composition that has fatigue resistance, mechanical characteristics and dynamic characteristics which are equal to those of a diene- based rubber such as natural rubber, and at the same time, is excellent in heat resistance and weather resistance. SOLUTION: The rubber composition comprises (A) an ethylene/3-20C α-olefin/ non-conjugated polyene copolymer, (B) a fine powdered silicic acid and/or a fine powdered silicate each having a specific surface area of 5-500 m<2> /g (BET adsorption: ISO 5794/1, Annex D), (C) at least one metal salt of an α,β-unsaturated carboxylic acid, (D) an organic peroxide, and if necessary, further comprises (E) at least one antiaging agent selected from a sulfur type antiaging agent, a phenol type antiaging agent and an amine type antiaging agent and/or (F) a composition comprising sulfur. The rubber product is produced by crosslinking the rubber composition.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention is excellent in mechanical characteristics, heat resistance and fatigue resistance, and also in dynamic characteristics.
That is, the present invention relates to a rubber composition containing an ethylene-C3-20 α-olefin-non-conjugated polyene copolymer, which has a low tan δ value and is suitable for applications such as automobile tires and anti-vibration rubber materials.

[0002]

2. Description of the Related Art Diene rubbers such as natural rubber (NR), styrene-butadiene rubber (SBR) and butadiene rubber (BR) are known as rubbers having excellent dynamic fatigue resistance and dynamic characteristics, and are used for automobile tires. It is also used as a raw material rubber for anti-vibration rubber. However, recently, the environment in which these rubber products are used has changed greatly, and there is a demand for improvement in heat resistance and weather resistance of the rubber products. In automobile tires, treads and tire sidewalls are particularly required to have weather resistance. However, there has been no rubber having the excellent mechanical properties, fatigue resistance and dynamic properties of the current diene rubber and having good weather resistance.

Therefore, a diene rubber excellent in mechanical properties, dynamic fatigue resistance and dynamic properties and an ethylene-carbon such as ethylene-propylene-non-conjugated diene copolymer rubber (EPDM) excellent in heat resistance and weather resistance. Various blend-type rubber compositions with an α-olefin-non-conjugated polyene copolymer of several 3 to 20 have been conventionally studied. However, the ethylene-C3-20 α-olefin-non-conjugated polyene copolymer has a different level of dynamic properties from that of the diene rubber, and therefore exhibits uniform physical properties. No blended rubber composition has hitherto been obtained. The dynamic characteristics of automobile tires depend on whether or not they are materials that do not deteriorate fuel consumption. The index is t
an δ (loss tangent) value, and the lower the tan δ value, the better the dynamic characteristics.

On the other hand, regarding anti-vibration rubber products for automobiles,
As the temperature inside the engine room has risen, vibration-resistant rubber products based on natural rubber, which is the current diene rubber, are no longer able to achieve fatigue resistance that can withstand practical use. Therefore, a new rubber material having excellent heat resistance and having mechanical properties, dynamic properties and fatigue resistance equal to or higher than that of the diene rubber has been desired.

Generally, in order to improve the dynamic characteristics,
It is necessary to increase the crosslink density. However, in the existing technology, when it is attempted to match the dynamic characteristics of an ethylene-C3-20 α-olefin-non-conjugated polyene copolymer with the dynamic characteristics of a diene rubber such as NR, the crosslinking density is It became too high, resulting in poor mechanical properties such as tensile elongation at break, and it was not possible to make physical properties compatible with dynamic properties.

[0006]

SUMMARY OF THE INVENTION The present invention is intended to solve the problems associated with the prior art as described above, and has fatigue resistance and mechanical properties equivalent to those of diene rubber such as natural rubber. Another object of the present invention is to provide a rubber composition having excellent heat resistance and weather resistance as well as having dynamic characteristics.

[0007]

Means for Solving the Problems The inventors of the present invention have made extensive studies in order to solve the above problems, and have excellent heat resistance. Ethylene-C3-20 α-olefin-non-conjugated polyene copolymer By using the combination and a specific finely divided silicic acid and / or silicate and at least one α, β-unsaturated carboxylic acid metal salt, finely divided silicic acid and / or silicate and a polymer, that is, ethylene-carbon The interaction with the α-olefin-non-conjugated polyene copolymer of Formula 3 to 20 is strengthened through at least one α, β-unsaturated carboxylic acid metal salt, and if necessary, further sulfur-based aging prevention Agent, a phenolic anti-aging agent and an amine anti-aging agent, and at least one anti-aging agent, and / or sulfur are compounded, and the obtained rubber composition is cross-linked with an organic peroxide, which is an antinomy. The dynamic characteristics and mechanical properties in engagement both can be improved, and found that a rubber product having excellent heat aging resistance can be obtained, and have completed the present invention.

That is, the present invention includes the following inventions. (1) (A) 100 parts by weight of ethylene-C3-C20 α-olefin-non-conjugated polyene copolymer, and (B) specific surface area of 5 to 500 m ² / g (BET adsorption amount: ISO5794 /
1, Annex D) Finely divided silicic acid and / or silicate 5
90 parts by weight, (C) 0.1 to 20 parts by weight of at least one α, β-unsaturated carboxylic acid metal salt, and (D) 0.1 to 15 parts by weight of organic peroxide. Composition. (2) (E) At least one selected from sulfur-based antioxidants, phenol-based antioxidants and amine-based antioxidants
The composition according to (1) above, which comprises a seed anti-aging agent. (3) The composition according to (1) or (2), which contains (F) sulfur. (4) (A) the ethylene-C3-20 α-olefin-non-conjugated polyene copolymer has a Mooney viscosity (MS
_{1 + 4} , 160 ° C.) 30 to 100 (1) to
The composition according to any one of (3). (5) (C) At least one α, β-unsaturated carboxylic acid metal salt is at least one compound selected from acrylic acid metal salts, methacrylic acid metal salts and maleic acid metal salts (1) to The composition according to any one of (4). (6) (G) contains a compound containing at least one unsaturated hydrocarbon group and at least one hydrolyzable silyl group, the content of which is (B) finely divided silicic acid and / or silicate The composition according to any one of (1) to (5), which has a surface area of less than 8 × 10 ⁻⁶ mol per 1 m ² . (7) A rubber product obtained by crosslinking the composition described in (1) to (6) above. (8) The rubber product according to (7), which is a vibration-proof rubber.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The composition of the present invention and the vulcanized rubber obtained from the composition are specifically described below.
First, the composition of the present invention will be described. The composition of the present invention comprises an ethylene-C3-C20 α-olefin-non-conjugated polyene copolymer, a specific finely divided silicic acid and / or silicate, and at least one α, β-unsaturation. A carboxylic acid metal salt, an organic peroxide, and, if necessary, at least one antioxidant and / or sulfur selected from sulfur-based antioxidants, phenol-based antioxidants and amine-based antioxidants. I will do it.

Ethylene-alpha-olefin having 3 to 20 carbon atoms
Ethylene -non-conjugated polyene copolymer The ethylene-C3-C20 α-olefin-non-conjugated polyene copolymer used in the present invention is a rubber composition capable of providing a vulcanized rubber molded article having excellent heat resistance and weather resistance. From the viewpoint of obtaining a product, (a) a unit derived from ethylene and (b) a unit derived from an α-olefin having 3 to 20 carbon atoms are 50/50 to 90/10 [(a) / (b)]. It is preferable to contain them in a molar ratio of. The molar ratio [(a) /
(B)] is more preferably 50/50 to 80/20.

The ethylene-C3-20 α-olefin-non-conjugated polyene copolymer has C3-2.
As the α-olefin having 0, an α-olefin having 3 to 12 carbon atoms is preferable, and specifically, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-
Pentene, 1-heptene, 1-octene, 1-nonene,
1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1
-Nonadecene, 1-eicosene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-
Tetradecene etc. are mentioned. These α-olefins can be used alone or in combination of two or more. Among these α-olefins, α-olefins having 3 to 8 carbon atoms, such as propylene, 1-butene, 4-
Methyl-1-pentene, 1-hexene, 1-octene are particularly preferred.

Specific examples of the non-conjugated polyene in the ethylene-C3-C20 α-olefin-non-conjugated polyene copolymer include 1,4-hexadiene, 1,
6-octadiene, 2-methyl-1,5-hexadiene, 6-methyl-1,5-heptadiene, 7-methyl-
Chain non-conjugated dienes such as 1,6-octadiene; cyclohexadiene, dicyclopentadiene, methyltetrahydroindene, 5-vinyl-2-norbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5- Isopropylidene-2-norbornene, 6
Cyclic non-conjugated dienes such as -chloromethyl-5-isopropenyl-2-norbornene; 2,3-diisopropylidene-5-norbornene, 2-ethylidene-3-isopropylidene-5-norbornene, 2-propenyl-2, 5-
Norbornadiene, 1,3,7-octatriene, 1,
4,9-decatriene, 4,8-dimethyl-1,4,8
-Decatriene, 4-ethylidene-8-methyl-1,7
-Trienes such as nonadiene. Among them, 1,
4-hexadiene and cyclic non-conjugated diene, particularly 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene, or a quaternary polymer in which 5-ethylidene-2-norbornene and 5-vinyl-2-norbornene are used in combination is preferable. Used. In the present invention, as the non-conjugated polyene, 5-ethylidene-2-norbornene, 5-vinyl-2-norbornene, or a quaternary polymer in which 5-ethylidene-2-norbornene and 5-vinyl-2-norbornene are used in combination is used. At this time, a rubber composition and vulcanized rubber having the best fatigue resistance can be obtained. The ethylene-C3-C20 α-olefin-non-conjugated polyene copolymer used in the present invention has an iodine value which is an index of the non-conjugated polyene content of usually 8 to 50, preferably 8 to 30. Is.

The ethylene used in the present invention has 3 to 3 carbon atoms.
The α-olefin-non-conjugated polyene copolymer of 20 has a Mooney viscosity MS _{1 + 4} (160 ° C.) of usually 30 to 100,
It is preferably 50 to 80. In the present invention, when an ethylene-C3-20 α-olefin-non-conjugated polyene copolymer having a Mooney viscosity MS _{1 + 4} (160 ° C.) in the above range is used, a diene-based polymer such as natural rubber is used. It is possible to obtain a rubber composition and a vulcanized rubber exhibiting fatigue resistance equal to or higher than that of rubber.

In the present invention, the above-mentioned ethylene-C3-C20 α-olefin-non-conjugated polyene copolymer can be used alone as the rubber component, but other rubber or plastic is further compounded. You may use it. For example, a blend of the copolymer rubber and the diene rubber can be used.

Specific examples of the diene rubber include natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene-butadiene rubber (SB).
R), acrylonitrile-butadiene rubber (NBR),
Examples include chloroprene rubber (CR). Above all,
Natural rubber and isoprene rubber are preferred. The above-mentioned diene rubbers may be used alone or in combination. As the plastic, specifically, crystalline polypropylene,
Examples thereof include polyolefin resins such as poly (4-methyl-1-pentene), nylon, polyester, and polycarbonate. When a diene rubber is used in the present invention, the amount used is ethylene-α-C3-20 α-
It is usually 20 to 50 parts by weight with respect to 100 parts by weight of the olefin-non-conjugated polyene copolymer.

[0016]Finely powdered silicic acid and / or silicate The finely divided silicic acid and finely divided silicate used in the present invention have a ratio of
Surface area is 5-500m ²/ G (BET adsorption amount: ISO 5794 /
1, Annex D), preferably 10-400m²/ G.
Examples of the finely divided silicic acid and the finely divided silicate include dry type
Method silica, wet method silica, synthetic silicate silica, etc.
Can be mentioned. Examples of silicates include magnesia silicate.
Umm. In the present invention, finely divided silicic acid and
It is also possible to use finely divided silicates each alone.
It is also possible to use these in combination.

In the present invention, the total amount of finely divided silicic acid and / or silicate is 5 to 90 parts by weight with respect to 100 parts by weight of ethylene-C 3-20 α-olefin-non-conjugated polyene copolymer. Parts, preferably 20 to 80 parts by weight. Further, when the composition of the present invention is used in a vibration-proof rubber product, it is required to have a dynamic characteristic in which a vibration damping effect is exhibited depending on the use of the vibration-proof rubber product. The compounding ratio of silicic acid and / or silicate will be adjusted before use.

Α, β-Unsaturated Carboxylic Acid Metal Salt The α, β-unsaturated carboxylic acid metal salt used in the present invention is preferably selected from acrylic acid metal salts, methacrylic acid metal salts and maleic acid metal salts. At least one compound may be mentioned.

Examples of the above-mentioned metal salts of acrylic acid, metal salts of methacrylic acid and metal salts of maleic acid include alkali metal salts of acrylic acid, methacrylic acid and maleic acid (eg lithium salt, sodium salt, potassium salt), alkali Earth metal salts (eg, magnesium salts, calcium salts), heavy metal salts (eg, zinc salts), aluminum salts,
Specifically, lithium acrylate, sodium acrylate, potassium acrylate, magnesium diacrylate,
Calcium diacrylate, zinc diacrylate, aluminum triacrylate, lithium methacrylate, sodium methacrylate, potassium methacrylate, magnesium dimethacrylate, calcium dimethacrylate, zinc dimethacrylate, aluminum trimethacrylate, lithium maleate, malein Examples thereof include sodium acid salt, potassium maleate, magnesium maleate, zinc maleate and aluminum maleate. As the α, β-unsaturated carboxylic acid metal salt, zinc dimethacrylate is particularly preferable.

In the present invention, the α, β-unsaturated carboxylic acid metal salt is ethylene-α-olefin having 3 to 20 carbon atoms.
0.1 to 100 parts by weight of non-conjugated polyene copolymer
-20 parts by weight, preferably 0.2-10 parts by weight. By using the α, β-unsaturated carboxylic acid metal salt, a polymer, that is, ethylene-C3-20
The interaction of the α-olefin-non-conjugated polyene copolymer with the finely divided silicic acid and the finely divided silicate is improved, and a crosslinked rubber product excellent in dynamic properties and mechanical properties can be obtained.
The α, β-unsaturated carboxylic acid metal salt may be used alone or in combination of two or more kinds.

Antiaging Agent In the present invention, when an antiaging agent is used, at least one selected from sulfur antiaging agents, phenol antiaging agents and amine antiaging agents is used. As the sulfur anti-aging agent, a sulfur anti-aging agent usually used for rubber is used.

Specific examples of the sulfur anti-aging agent include 2-mercaptobenzimidazole, zinc salt of 2-mercaptobenzimidazole, 2-mercaptomethylbenzimidazole, zinc salt of 2-mercaptomethylbenzimidazole, 2-mercaptomethylbenzimidazole and 2-mercaptomethylbenzimidazole. Imidazole type anti-aging agents such as mercaptomethylimidazole zinc salt; dimyristyl thiodipropionate, dilauryl thiodipropionate, distearyl thiodipropionate, ditridecyl thiodipropionate, pentaerythritol-tetrakis (β-lauryl) -Thiopropionate) and other aliphatic thioether anti-aging agents.
Of these, 2-mercaptobenzimidazole, zinc salt of 2-mercaptobenzimidazole, 2-
Mercaptomethylbenzimidazole, zinc salt of 2-mercaptomethylbenzimidazole, pentaerythritol-tetrakis (β-lauryl-thiopropionate) are preferred. As the phenol-based antioxidant, a phenol-based antioxidant commonly used for rubber is used.

Specific examples of the phenol anti-aging agent include styrenated phenol, 2,6-di-t-butylphenol, 2,6-di-t-butyl-4-methylphenol and 2,6-diphenol. -T-butyl-4-ethylphenol, 2,4,6-tri-t-butylphenol, butylhydroxyanisole, 1-hydroxy-3-methyl-
4-isopropylbenzene, mono-t-butyl-p-cresol, mono-t-butyl-m-cresol, 2,4
-Dimethyl-6-t-butylphenol, butylated bisphenol A, 2,2'-methylene-bis (4-methyl-6-t-butylphenol), 2,2'-methylene-
Bis (4-ethyl-6-t-butylphenol), 2,
2'-methylene-bis (4-methyl-6-t-nonylphenol), 2,2'-isobutylidene-bis (4,6
-Dimethylphenol), 4,4'-butylidene-bis (3-methyl-6-t-butylphenol), 4,4 '
-Methylene-bis (2,6-di-t-butylphenol), 2,2'-thio-bis (4-methyl-6-t-butylphenol), 4,4'-thio-bis (3-methyl-6) -T-butylphenol), 4,4'-thio-bis (2-methyl-6-butylphenol), 4,4'-thio-bis (6-t-butyl-3-methylphenol),
Bis (3-methyl-4-hydroxy-5-t-butylbenzene) sulfide, 2,2'-thio [diethyl-bis-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], Bis [3,3-bis (4-hydroxy-3-t-butylphenyl) butyric acid] glycol ester, bis [2- (2-hydroxy-5-methyl-3)
-T-butylbenzene) -4-methyl-6-t-butylphenyl] terephthalate, 1,3,5-tris (3,3)
5-di-t-butyl-4-hydroxybenzyl) isocyanurate, N, N′-hexamethylene-bis (3,5
-Di-t-butyl-4-hydroxyhydrocinnamamide), n-octadecyl 3- (4-hydroxy-3,
5-di-t-butylphenyl) propionate, tetrakis [methylene-3- (3,5-di-t-butyl-4-)
Hydroxyphenyl) propionate] methane, pentaerythritol-tetrakis [3- (3,5-di-t-)
Butyl-4-hydroxyphenyl) propionate],
1,1′-bis (4-hydroxyphenyl) cyclohexane, mono (α-methylbenzene) phenol, di (α
-Methylbenzyl) phenol, tri (α-methylbenzyl) phenol, 2,6-bis (2-hydroxy-3)
-T-butyl-5-methylbenzyl) -4-methylphenol, 3,9-bis [2- {3- (3-t-butyl-
4-Hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10
-Tetraoxaspiro [5.5] undecane, 2,5-
Di-t-amylhydroquinone, 2,6-di-t-butyl-α-dimethylamino-p-cresol, 2,5-di-t-butylhydroquinone, 3,5-di-t-butyl-4-hydroxy Diethyl ester of benzyl phosphate,
Examples include catechol and hydroquinone. Examples of particularly preferred phenolic anti-aging agents include 4,4 '
-Butylidene-bis (3-methyl-6-t-butylphenol), 4,4'-methylene-bis (2,6-di-t)
-Butylphenol), 2,2'-thio-bis (4-methyl-6-t-butylphenol), 4,4'-thio-
Bis (3-methyl-6-t-butylphenol), 4,
4'-thio-bis (2-methyl-6-butylphenol), 4,4'-thio-bis (6-t-butyl-3-methylphenol), tetrakis [methylene-3- (3,3.
5-di-t-butyl-4-hydroxyphenyl) propionate] methane, pentaerythritol-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 3,9-bis [2] -{3-
(3-t-Butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl]
Examples thereof include −2,4,8,10-tetraoxaspiro [5.5] undecane.

As the amine anti-aging agent, an amine anti-aging agent usually used for rubber is used. Specific examples of the amine-based antioxidant include naphthylamine-based antioxidants such as phenyl-α-naphthylamine and phenyl-β-naphthylamine; p- (p-toluenesulfonylamide) diphenylamine and 4,4′-bis ( α, α-
Dimethylbenzyl) diphenylamine, alkylated diphenylamine, octylated diphenylamine, dioctylated diphenylamine (eg 4,4′-dioctyldiphenylamine), high temperature reaction product of diphenylamine and acetone, low temperature reaction product of diphenylamine and acetone, diphenylamine and A diphenylamine-based antioxidant such as a low-temperature reaction product of aniline and acetone and a reaction product of diphenylamine and diisobutylene;
N, N'-diphenyl-p-phenylenediamine, n-
Isopropyl-N'-phenyl-p-phenylenediamine, N, N'-di-2-naphthyl-p-phenylenediamine, N-cyclohexyl-N'-phenyl-p-phenylenediamine, N-phenyl-N '-( 3-methacryloyloxy-2-hydroxypropyl) -p-phenylenediamine, N, N'-bis (1-methylheptyl)
-P-phenylenediamine, N, N'-bis (1,4-
Dimethylpentyl) -p-phenylenediamine, N,
N'-bis (1-ethyl-3-methylpentyl) p-phenylenediamine, N- (1,3-dimethylbutyl)-
N'-phenyl-p-phenylenediamine, phenylhexyl-p-phenylenediamine, phenyloctyl-
Examples thereof include p-phenylenediamine antiaging agents such as p-phenylenediamine. Among these, especially 4,
4′-bis (α, α-dimethylbenzyl) diphenylamine, N, N′-diphenyl-p-phenylenediamine and N, N′-di-2-naphthyl-p-phenylenediamine are preferred.

In the present invention, the sulfur anti-aging agent, the phenol anti-aging agent and the amine anti-aging agent may be used alone, but in view of maintaining heat aging resistance for a long time at high temperature, It is preferable to use two or more kinds in combination. In the present invention, the sulfur-based antioxidant is usually 0.2 to 10 parts by weight, preferably 0.2 to 100 parts by weight of the ethylene-C3-20 α-olefin-non-conjugated polyene copolymer. -8 parts by weight, more preferably 0.
It is used in a proportion of 2 to 6 parts by weight. When the sulfur-based antioxidant is used in the above proportion, the effect of improving the heat aging resistance is great and the crosslinking of the copolymer rubber is not hindered.

The phenol-based antioxidant is usually 0.2 to 5 parts by weight, preferably 0.5 to 100 parts by weight with respect to 100 parts by weight of an ethylene-C3-20 α-olefin-non-conjugated polyene copolymer. 4 parts by weight, more preferably 0.5 to 3 parts by weight. When the phenolic antiaging agent is used in the above proportion, the effect of improving the heat aging resistance is great, and the crosslinking of the copolymer rubber is not hindered.

The amine anti-aging agent is an ethylene-C3-C20 α-olefin-non-conjugated polyene copolymer 1
It is usually used in an amount of 0.05 to 5 parts by weight, preferably 0.1 to 4 parts by weight, and more preferably 0.2 to 3 parts by weight with respect to 00 parts by weight. When the amine-based antiaging agent is used in the above proportion, the effect of improving the heat aging resistance is great,
Moreover, it does not hinder the crosslinking of the copolymer rubber.

Examples of the sulfur sulfur can be used a conventionally known sulfur that is usually used in the rubber crosslinking. Specific examples thereof include powdered sulfur, precipitated sulfur, colloidal sulfur, surface-treated sulfur, insoluble sulfur, and sulfur masterbatch compound in which they are dispersed in EPDM or an inorganic filler in advance.

Organic Peroxide As the organic peroxide, a conventionally known organic peroxide which is usually used in the cross-linking of rubber can be used.
Specifically, dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di- (tert
-Butylperoxy) hexane, 2,5-dimethyl-
2,5-di- (tert-butylperoxy) hexyne-
3,1,3-bis (tert-butylperoxyisopropyl) benzene, 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane, n-butyl-4,4-bis (tert-butyl) (Peroxy) valerate, benzoyl peroxide, p-chlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxyisopropyl carbonate, diacetyl peroxide, lauroyl peroxide, tert-butyl cumyl peroxide and the like. .

Such an organic peroxide obtains the desired physical properties by sufficient cross-linking, prevents adverse effects due to excessive decomposition products, and costs, so that an ethylene-α-olefin having 3 to 20 carbon atoms is used. Used in a proportion of 0.1 to 15 parts by weight based on 100 parts by weight of the non-conjugated polyene copolymer.

Other Components In the present invention, additives such as an inorganic filler other than the above-mentioned finely divided silicic acid and silicate can be blended in the rubber composition within the range not impairing the object of the present invention. . Specific examples of the inorganic filler other than the above-mentioned fine powder silicic acid and silicate include SRF, GPF, FEF, MAF, HAF,
Carbon black such as ISAF, SAF, FT, MT,
Usual fine powder silicic acid, light calcium carbonate, heavy calcium carbonate, talc, clay and the like can be mentioned. The specific surface area of such carbon black is preferably 5 to 200 m ² / g, and the specific surface area of the inorganic filler is 1 to 1
It is preferably 00 m ² / g.

In the composition of the present invention, the amount of carbon black used is 0.1 to 60 parts by weight based on 100 parts by weight of the ethylene-C3-20 α-olefin-non-conjugated polyene copolymer. Is preferred. In order to obtain a rubber composition having excellent dynamic characteristics and fatigue resistance, and a vulcanized rubber, the amount of the inorganic filler other than the finely divided silicic acid and the silicate used is the ethylene-α having 3 to 20 carbon atoms. 0 based on 100 parts by weight of olefin-non-conjugated polyene copolymer
It is preferable that the total amount of all the inorganic filler components is 0.1 to 100 parts by weight with respect to 100 parts by weight of the ethylene-C3-20 α-olefin-non-conjugated polyene copolymer. ~ 120 parts by weight, preferably 10-12
The amount is 0 parts by weight, more preferably 10 to 100 parts by weight.

A silane coupling agent can be added to the composition of the present invention. Of the silane coupling agents, γ-methacryloyloxypropyltrimethoxysilane, vinyltrimethoxysilane, vinyltris (β- Compounds containing at least one unsaturated hydrocarbon group and at least one hydrolyzable silyl group, such as (methoxyethoxy) silane, vinyltriethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, also serve as crosslinkers. Since it works, the content thereof is 8 × per 1 m ² of surface area of finely divided silicic acid and / or silicate from the viewpoint of ensuring an adequate crosslink density and sufficient elongation.
It is preferably less than 10 ^-6 mol, and 8 × 10 ^-7 m
More preferably, it is less than ol.

On the other hand, a silane coupling agent having no unsaturated hydrocarbon group, bis [3- (triethoxysilyl) propyl] tetrasulfide, etc. does not act as a cross-linking agent, and therefore finely divided silicic acid and / or silicate. Surface area of 1 m ²
Therefore, it can be usually compounded at a ratio of less than 1 × 10 ⁻³ mol.

The composition of the present invention is added to the composition which is usually used for sulfur vulcanizing an ethylene-C3-C20 α-olefin-non-conjugated polyene copolymer within a range that does not impair the object of the present invention. A sulfur accelerator can be added. Specific examples of the vulcanization accelerator include N-cyclohexyl-2-benzothiazole sulfenamide, N-oxydiethylene-2-benzothiazole sulfenamide,
N, N-diisopropyl-2-benzothiazole sulfenamide, 2-mercaptobenzothiazole, 2-
(2,4-Dinitrophenyl) mercaptobenzothiazole, 2- (2,6-diethyl-4-morpholinothio)
Thiazole compounds such as benzothiazole and dibenzothiazyl disulfide; guanidine compounds such as diphenylguanidine, triphenylguanidine, diorthotolylguanidine, orthotril biguanide, diphenylguanidine phthalate; acetaldehyde-aniline reaction product, butyraldehyde- Aldehyde-amines or aldehyde-ammonia compounds such as aniline reaction products, hexamethylenetetramine, acetaldehyde-ammonia reaction products; imidazoline compounds such as 2-mercaptoimidazoline; thiocarbanilide, diethylthiourea, dibutylthiourea, trimethylthiourea, diorthotolylthiourea. And other thiourea compounds; tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tet A thiuram compound such as ethyl thiuram disulfide, tetrabutyl thiuram disulfide, pentamethylene thiuram tetrasulfide; zinc dimethyldithiocarbamate, zinc diethyldithiocarbamate, zinc di-n-butyldithiocarbamate, zinc ethylphenyldithiocarbamate, zinc butylphenyldithiocarbamate. Dithiocarbamate salts such as sodium dimethyldithiocarbamate, selenium dimethyldithiocarbamate, and tellurium diethyldithiocarbamate;
Xanthate salts such as zinc dibutylxanthate; and other compounds such as zinc oxide (zinc oxide).

The vulcanization accelerator is used in an amount of 0 to 20 parts by weight per 100 parts by weight of the rubber component, that is, the ethylene-C3-20 α-olefin-non-conjugated polyene copolymer.
It is preferably used in a proportion of 0 to 10 parts by weight.

Method for Producing Vulcanized Rubber To obtain a vulcanized rubber from the composition of the present invention, an unvulcanized compounded rubber (rubber composition ) Is once prepared, and then the compounded rubber is molded into an intended shape and then vulcanized.

In producing the vulcanized rubber according to the present invention, depending on the intended use of the vulcanized rubber and the performance based thereon, the above-mentioned rubber component, finely divided silicic acid and / or silicate, α, β are used.
-Unsaturated carboxylic acid metal salts, sulfur-based antioxidants, phenol-based antioxidants, amine-based antioxidants, organic peroxides, as well as types and blending amounts of softeners, and further vulcanization aids, etc. The type and amount of the compound constituting the vulcanization system and the step of producing the vulcanized rubber are appropriately selected.

As the softening agent, a softening agent usually used for rubber is used. Specifically, petroleum-based softening agents such as process oil, lubricating oil, liquid paraffin, petroleum asphalt, vaseline; coal tar, coal. Coal tar-based softeners such as tar pitch; castor oil, linseed oil,
Fat oil softeners such as rapeseed oil, soybean oil and coconut oil; tall oil; sub (factis); waxes such as beeswax, carnauba wax, lanolin; ricinoleic acid, palmitic acid, stearic acid, barium stearate, calcium stearate Fatty acids and fatty acid salts such as zinc laurate; synthetic polymer substances such as petroleum resin, atactic polypropylene and coumarone indene resin are used alone or in combination of two or more kinds. Among them, petroleum-based softeners, especially process oils are preferably used. These softeners are
0-100 with respect to 100 parts by weight of the ethylene-C3-20 α-olefin-non-conjugated polyene copolymer.
It can be used in a proportion of parts by weight, preferably 2 to 80 parts by weight.

The unvulcanized compounded rubber is prepared, for example, by the following method. That is, using a mixer such as a Banbury mixer, the above-mentioned rubber component, finely divided silicic acid and / or silicate, and further other inorganic fillers and softeners at a temperature of 80 to 190 ° C. for 2 to 20 minutes. After kneading, and then using rolls such as an open roll, the organic peroxide and at least one α, β-unsaturated carboxylic acid metal salt are mixed, and the roll temperature is 40 to 60 ° C. for 3 to 30 minutes. After kneading, the kneaded product is extruded to prepare a ribbon-shaped or sheet-shaped compounded rubber.

The compounded rubber thus prepared is molded into an intended shape by an extruder, a calender roll or a press, and at the same time as molding or by introducing the molded product into a vulcanization tank, usually at 100 to 270 ° C. It is usually heated at a temperature for 1 to 150 minutes to obtain a vulcanized rubber. When performing such vulcanization,
A mold may or may not be used. When a mold is not used, the molding and vulcanization steps are usually carried out continuously.

The vulcanized rubber obtained from the composition of the present invention is
Widely used in various rubber products such as tires, automobile parts, general industrial parts, and civil engineering building materials. In particular, it can be suitably used for applications requiring dynamic fatigue resistance, for example, tire treads, tire sidewalls, wiper blades, anti-vibration rubbers for automobile engine mounts, and the like.

[0043]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. In addition, the test methods of various physical properties in Examples and Comparative Examples,
It is as follows.

[Iodine Value] The iodine value of the copolymer rubber is
It was determined by a titration method. [Moonie viscosity] The Mooney viscosity was measured according to JIS K6300 using an S-type rotor at a measurement temperature of 160 ° C. [Tensile test / Hardness test] In accordance with JIS K6251
A tensile test was performed under the conditions of a measurement temperature of 23 ° C. and a tensile speed of 500 mm / min to measure the strength T _B at break, the elongation E _B, and the hardness H _A. [Heat resistance aging test] In accordance with JIS K6257, 1
Air heating aging for 70 hours and 200 hours at a temperature of 50 ° C., and measuring the tensile strength and elongation at break after aging,
Retention rate (%) against the original value that has not been aged
Indicated by. [Compression set test] A compression set test was performed according to JIS K6262. [Evaluation of dynamic properties (tan δ)] The test of dynamic properties (dynamic viscoelasticity test) is based on JIS K6394, and a viscoelasticity tester (type RD) manufactured by Rheometrics.
S-II) was used to determine tan δ at a frequency of 10 Hz and 1 Hz under the conditions of a measurement temperature of 25 ° C. and a strain rate of 1%.

The ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber, finely divided silicic acid, and other compounding agents used in Examples and Comparative Examples are as follows. (1) Ethylene-propylene-5-ethylidene-2-norbornene copolymer rubber (EPT)

[0046]

[Table 1]

(2) Fine silicic acid

[0048]

[Table 2]

(3) Anti-aging agent A 2-mercaptobenzimidazole (4) Anti-aging agent B pentaerythritol-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] (5) Anti-aging agent C 4,4′-bis (α, α-dimethylbenzyl) diphenylamine

Example 1 EPT 100 shown in Table 1
Parts by weight, paraffinic process oil [Idemitsu Kosan Co., Ltd.
Manufactured by PW-380] 50 parts by weight, zinc flower No. 1 5 parts by weight,
1 part by weight of stearic acid, 5 parts by weight of MAF carbon black [SEAST G116 manufactured by Tokai Carbon Co., Ltd.], 45 parts by weight of finely divided silicic acid (Ultrasil 360 manufactured by Degussa Hüls), 4 parts by weight of anti-aging agent A and anti-aging 2 parts by weight of the agent B was kneaded using a Banbury mixer [Mixtron mixer manufactured by Kobe Steel, Ltd.] having a capacity of 2.95 liters.

The kneaded product thus obtained is treated at about 50 ° C.
After cooling to 8,000, kayak mill D-40C [dicumyl peroxide diluted to 40% with calcium carbonate, manufactured by Kayaku Akzo Co., Ltd.] 6.8 parts by weight and zinc dimethacrylate (ZMA) After adding 2 parts by weight and kneading with an 8-inch roll (front and rear roll temperature: 50 ° C.), the mixture was dispensed into a sheet and pressed at 170 ° C. for 15 minutes to obtain a vulcanized sheet having a thickness of 2 mm. The physical properties were evaluated according to the methods described above. In addition, the pressing condition is set to 170
A thick vulcanized rubber molded product for compression set testing was obtained at 20 ° C. for 20 minutes, and a compression set test was performed on this thick vulcanized rubber molded product. The results are shown in Table 3.

Comparative Example 1 Zinc dimethacrylate (ZM
A) instead of triallyl isocyanurate (TAI
A vulcanized rubber molded product was obtained by the same composition and molding conditions as in Example 1 except that C) was used, and the physical properties were evaluated. The results are shown in Table 3.

Comparative Example 2 Zinc dimethacrylate (ZM
A) instead of triallyl isocyanurate (TAI
C) and γ-methacryloyloxypropyltrimethoxysilane (silane coupling agent) were added in an amount of 0.5 part by weight, and a vulcanized rubber molded product was obtained according to the same composition and molding conditions as in Example 1, An evaluation was made. The results are shown in Table 3.

(Example 2) Zinc dimethacrylate (ZM
A vulcanized rubber molded product was obtained by the same compounding and molding conditions as in Example 1 except that the compounding amount of A) was changed to 1 part by weight and the compounding amount of the antioxidant A was changed to 2 part by weight, and the physical properties were evaluated. went. The results are shown in Table 3.

Example 3 A vulcanized rubber molded product was obtained by the same compounding and molding conditions as in Example 2, except that the compounding amount of KAYAKU MILL D-40C was changed to 8.5 parts by weight, and the physical properties were evaluated. . The results are shown in Table 3.

Example 4 A vulcanized rubber molded product was obtained by the same composition and molding conditions as in Example 1 except that 2 parts by weight of the antioxidant C was used in place of the antioxidant A, and the physical properties were evaluated. It was The results are shown in Table 3.

Example 5 EPT 100 shown in Table 1
Parts by weight, paraffinic process oil [Idemitsu Kosan Co., Ltd.
Manufactured by PW-380] 60 parts by weight, zinc flower No. 1 5 parts by weight,
Stearic acid 1 part by weight, MAF carbon black [Tokai Carbon Co., Ltd., Seast G116] 5 parts by weight, fine powder silicic acid (Wacker HDK N20P) 35 parts by weight,
2 parts by weight of anti-aging agent A and 2 parts by weight of anti-aging agent B were kneaded using a Banbury mixer [Mixtron mixer manufactured by Kobe Steel, Ltd.] having a capacity of 2.95 liters.

The kneaded material thus obtained is heated to about 50 ° C.
After cooling to 8,000, kayak mill D-40C [dicumyl peroxide diluted to 40% with calcium carbonate, manufactured by Kayaku Akzo Co., Ltd.] 6.8 parts by weight and zinc dimethacrylate (ZMA) After adding 2 parts by weight and kneading with an 8-inch roll (front and rear roll temperature: 50 ° C.), the mixture was dispensed into a sheet and pressed at 170 ° C. for 15 minutes to obtain a vulcanized sheet having a thickness of 2 mm. The physical properties were evaluated according to the methods described above. In addition, the pressing condition is set to 170
A thick vulcanized rubber molded product for compression set testing was obtained at 20 ° C. for 20 minutes, and a compression set test was performed on this thick vulcanized rubber molded product. The results are shown in Table 3.

Example 6 A vulcanized rubber molded product was obtained by the same compounding and molding conditions as in Example 5, except that the compounding amount of HDK N20P was changed to 30 parts by weight, and the physical properties were evaluated. The results are shown in Table 3.

Example 7 EPT 100 shown in Table 1
Parts by weight, paraffinic process oil [Idemitsu Kosan Co., Ltd.
Manufactured by PW-380] 55 parts by weight, zinc flower No. 1 5 parts by weight,
Stearic acid 1 part by weight, MAF carbon black [Tokai Carbon Co., Ltd., Seast G116] 5 parts by weight, finely divided silicic acid (JM Huber Zeopole 87)
15) 35 parts by weight, 2 parts by weight of anti-aging agent A and 2 parts by weight of anti-aging agent B were kneaded using a Banbury mixer [Mixtron mixer manufactured by Kobe Steel Ltd.] having a capacity of 2.95 liters.

The kneaded product thus obtained is heated to about 50 ° C.
After cooling to 8,000, kayak mill D-40C [dicumyl peroxide diluted to 40% with calcium carbonate, manufactured by Kayaku Akzo Co., Ltd.] 6.8 parts by weight and zinc dimethacrylate (ZMA) After adding 2 parts by weight and kneading with an 8-inch roll (front and rear roll temperature: 50 ° C.), the mixture was dispensed into a sheet and pressed at 170 ° C. for 15 minutes to obtain a vulcanized sheet having a thickness of 2 mm. The physical properties were evaluated according to the methods described above. In addition, the pressing condition is set to 170
A thick vulcanized rubber molded product for compression set testing was obtained at 20 ° C. for 20 minutes, and a compression set test was performed on this thick vulcanized rubber molded product. The results are shown in Table 4.

(Example 8) A vulcanized rubber molded product was obtained by the same compounding and molding conditions as in Example 7, except that the compounding amount of KAYAKUMIL D-40C was changed to 8.5 parts by weight, and the physical properties were evaluated. . The results are shown in Table 4. (Example 9) The compounding amount of Zeopole 8715 was 30
A vulcanized rubber molded product was obtained by the same composition and molding conditions as in Example 7, except that the amount was changed to parts by weight, and the physical properties were evaluated. The results are shown in Table 4.

(Embodiment 10) Zeopole 8715
A vulcanized rubber molded product was obtained by the same composition and molding conditions as in Example 8 except that the compounding amount was changed to 30 parts by weight, and the physical properties were evaluated. The results are shown in Table 4. (Example 11) The compounding amount of Zeopole 8715 was 2
A vulcanized rubber molded product was obtained by the same composition and molding conditions as in Example 7, except that the amount was changed to 5 parts by weight, and the physical properties were evaluated.
The results are shown in Table 4.

Example 12 EPT 10 shown in Table 1
0 parts by weight, paraffin-based process oil [Idemitsu Kosan Co., Ltd., PW-380] 50 parts by weight, Zinc Hua No. 1 5 parts by weight, stearic acid 1 part by weight, MAF carbon black [Tokai Carbon Co., Ltd., SIST G116] 5 parts by weight, finely divided silicic acid (Zepol manufactured by JM Huber)
e 8715) 35 parts by weight, anti-aging agent A 2 parts by weight and zinc dimethacrylate (ZMA) 2 parts by weight in a volume of 2.
95-liter Banbury mixer [Kobe Steel Co., Ltd.
Mixtron mixer].

The kneaded product thus obtained is heated to about 50 ° C.
After cooling to 1, the kneaded product was 6.8 parts by weight of kayak mill D-40C [dicumyl peroxide diluted to 40% with calcium carbonate, manufactured by Kayaku Akzo Co., Ltd.] and 0.1 part by weight of powdered sulfur. 8 inch roll (front and rear rolls)
(Temperature: 50 ° C), and then dispensed into sheet form 1
A vulcanized sheet having a thickness of 2 mm was obtained by pressing at 70 ° C. for 15 minutes, and the vulcanized sheet was evaluated for its physical properties according to the methods described above. Further, the pressing conditions were set to 170 ° C. for 20 minutes to obtain a thick vulcanized rubber molded product for a compression set test, and the thick vulcanized rubber molded product was subjected to a compression set test. The results are shown in Table 4.

(Example 13) The blending amount of powdered sulfur was adjusted to 0.
A vulcanized rubber molded product was obtained by the same composition and molding conditions as in Example 12 except that the amount was changed to 2 parts by weight, and the physical properties were evaluated. The results are shown in Table 4. (Example 14) A vulcanized rubber molded product was obtained by the same compounding and molding conditions as in Example 12, except that the amount of powdered sulfur was changed to 0.3 part by weight, and the physical properties were evaluated. The results are shown in Table 4.
Shown in.

[0067]

[Table 3]

[0068]

[Table 4]

[0069]

The composition of the present invention has not only excellent dynamic properties but also excellent mechanical properties, dynamic fatigue resistance and heat aging resistance, and a vulcanized rubber having the above-mentioned effects. Products can be provided.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08K 5/14 C08K 5/14 5/36 5/36 5/5415 5/5415 (72) Inventor Hide Nakahama 3 Chichikaigan, Ichihara, Chiba Mitsui Chemicals Stock Company In-house (72) Inventor Masaaki Kawasaki 3 Chichikaigan, Ichihara City, Chiba Mitsui Chemicals Stock Company In-house F-term (reference) 4J002 BB051 BB151 DA049 DJ006 DJ016 EG027 EG037 EG057 EJ028 EV028 FD030 FD038 GM00 GN00 GN01

Claims (8)

[Claims] 1. (A) Ethylene-α-having 3 to 20 carbon atoms
100 parts by weight of olefin-non-conjugated polyene copolymer,
(B) Specific surface area of 5 to 500 m ² / g (BET adsorption amount: I
SO 5794/1, Annex D) 5 to 90 parts by weight of finely divided silicic acid and / or silicate, and (C) at least one α, β
-0.1 to 20 parts by weight of unsaturated carboxylic acid metal salt,
(D) A composition containing 0.1 to 15 parts by weight of an organic peroxide. 2. The composition according to claim 1, which comprises (E) at least one antioxidant selected from sulfur-based antioxidants, phenol-based antioxidants and amine-based antioxidants. 3. The method according to claim 1, which comprises (F) sulfur.
The composition according to. 4. (A) Ethylene-α-having 3 to 20 carbon atoms
The composition according to any one of claims 1 to 3, wherein the olefin-non-conjugated polyene copolymer has a Mooney viscosity (MS _{1 + 4} , 160 ° C) of 30 to 100. 5. The (C) at least one α, β-unsaturated carboxylic acid metal salt is at least one compound selected from acrylic acid metal salts, methacrylic acid metal salts and maleic acid metal salts. 5. The composition according to any one of items 1 to 4. 6. (G) A compound containing at least one unsaturated hydrocarbon group and at least one hydrolyzable silyl group, the content of which is (B) finely divided silicic acid and / or silicic acid. 8 × 10 ^-6 mo per 1 m ² of surface area of salt
The composition according to claim 1, which is less than 1. 7. A rubber product obtained by crosslinking the composition according to any one of claims 1 to 6. 8. The rubber product according to claim 7, which is a vibration-proof rubber.