Sumitomo Chemical Company, Limited

Other

Sadayuki Nakano

Ayumu Ikemoto

Takashi Nishida

Eiichi Daikai

Tatsuo Sassa

Kiyoshi Ikeda

Junichi Koshiba

Takashi Sakai

Tetsuji Takezawa

A rubber composition contains: (A) an ethylene-&#x3b1;-olefin-based copolymer rubber including an ethylene unit and an &#x3b1;-olefin unit having 3 or more carbon atoms; (B) a fire retardant including a phosphorus atom and a nitrogen atom; (C) a thermally expandable graphite; and (D) additive particles that are porous particles or particles having ion exchangeability. A content of the fire retardant is 50 to 250 parts by mass and a content of the additive particles is 15 parts by mass or less with respect to 100 parts by mass of the ethylene-&#x3b1;-olefin-based copolymer rubber.

Rubber composition, rubber molded body, and method for production of rubber molded body

The rubber composition contains the following component (A), the following component (B), and the following component (C). The component (A) is an ethylene-&#x3b1;-olefin-nonconjugated polyene copolymer rubber containing an ethylene unit, an &#x3b1;-olefin unit, and a nonconjugated polyene unit, a number of carbon atoms of the &#x3b1;-olefin unit is 3 to 20, a limiting viscosity measured in 135&#xb0; C. tetralin is 2.8 dl/g to 5 dl/g, a content of the ethylene unit is 70 mol % to 90 mol % (where a total of the content of the ethylene unit and a content of the &#x3b1;-olefin unit in the component (A) is 100 mol %), and a content of the nonconjugated polyene unit is 2 wt % to 20 wt % (where a total amount of the component (A) is 100 wt %); the component (B) is an organic peroxide; and the component (C) is a thermosetting prepolymer.

Rubber composition and molded article

Provided is an ethylene-&#x3b1;-olefin-nonconjugated polyene copolymer having ethylene units, &#x3b1;-olefin units and nonconjugated polyene units, wherein the copolymer satisfies the following requirements: (A): the intrinsic viscosity [&#x3b7;] is 0.5 to 1.8 dl/g, (B): the content of ethylene units is 50 to 90 mol % and the content of &#x3b1;-olefin units is 50 to 10 mol % where the sum total of the contents of ethylene units and &#x3b1;-olefin units is taken as 100 mol %, (C): the iodine value is 1 to 50, (D): the ratio of tan &#x3b4; taken at 100&#xb0; C. and 2 cpm to tan &#x3b4; taken at 100&#xb0; C. and 1000 cpm is from 1.0 to 1.7, and (E): the ratio of the Z-average molecular weight to the number average molecular weight is from 15 to 25 and the weight average molecular weight to the number average molecular weight is from 3 to 5.

Ethylene-&#x3b1;-olefin-nonconjugated polyene copolymer

The copolymer rubber composition comprises 60 to 75% by weight of a copolymer rubber (1) and 40 to 25% by weight of a copolymer rubber (2), and exhibits a difference in iodine value of 5 to 30 between the copolymer rubber (1) and the copolymer rubber (2). The copolymer rubber (1) is an ethylene-&#x3b1;-olefin-nonconjugated polyene copolymer rubber having an ethylene unit of 50 mol % to 70 mol %, an &#x3b1;-olefin unit of 50 mol % to 30 mol %, and an iodine value of 10 to 30, and the copolymer rubber (2) is an ethylene-&#x3b1;-olefinic copolymer rubber having an ethylene unit of more than 70 mol % and 95 mol % or less, an &#x3b1;-olefin unit of less than 30 mol % and 5 mol % or more, and an iodine value of 0 to 8.

Copolymer rubber composition, molded product, and automotive sealant

The copolymer rubber composition comprises 60 to 75% by weight of a copolymer rubber (1) and 40 to 25% by weight of a copolymer rubber (2), and [iodine value of the copolymer rubber (1)&#x2212;iodine value of the copolymer rubber (2)] is 5 to 30. The copolymer rubber (1) is an ethylene-&#x3b1;-olefin-nonconjugated polyene copolymer rubber having an ethylene unit of 50 mol % to 70 mol %, an &#x3b1;-olefin unit of 50 mol % to 30 mol %, and an iodine value of 15 to 45, and the copolymer rubber (2) is an ethylene-&#x3b1;-olefinic copolymer rubber having an ethylene unit of more than 70 mol % and 95 mol % or less, an &#x3b1;-olefin unit of less than 30 mol % and 5 mol % or more, and an iodine value of 10 to 30.

Copolymer rubber composition, rubber foamed product, and automotive sealant

A process for producing a vulcanized molded article of a rubber composition, which comprises the steps of (1) kneading, at least, 100 parts by weight of a defined ethylene-&#x3b1;-olefin-non-conjugated polyene copolymer rubber (A), 1 to 150 parts by weight of a reinforcement (B), and 1 to 150 parts by weight of a softener (C), (2) mixing the resultant kneaded product with 0.1 to 10 parts by weight of a vulcanizing agent (D), and (3) hot forming the resultant rubber composition; and a vibration-proof material comprising a vulcanized molded article of a rubber composition produced by the above process.

Process for producing vulcanized molded article of rubber composition, and vibration-proof material

Vulcanized solid rubber

A rubber composition containing (A) an ethylene-&agr;-olefin based copolymer rubber having an intrinsic viscosity &lsqb;&eegr;&rsqb; of 2.0-10.0 as determined in xylene at 70&deg; C., (B) a softening agent, and (C) a filler, which composition is superior in heat resistance and fatigue resistance, is obtained by a process including the steps of dividing component (A) into portions (A ) and (A ), dividing component (B) into portions (B ) and (B ), dividing component (C) into portions (C ) and (C ), kneading portions (A ), (B ) and (C ) together to obtain a first blend, adding portions (A ), (B ) and (C ) to the first blend to obtain a second blend and kneading the second blend to obtain the rubber composition.

Process for producing rubber composition and rubber composition

Rubber composition and vulcanized rubber composition

Rubber compositions and products devoid of zinc

A rubber composition comprising the following components (A) to (C) and comprising no zinc-containing compound:

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Ichihara, Japan

Sadayuki Nakano