Abstract: The present invention provides a molded product exhibiting excellent various properties by improving compatibility of an ethylene/?-olefin/non-conjugated polyene copolymer with a polyolefin resin and a rubber composition for forming the molded product. The present invention further provides a molded product which comprises a rubber composition, is inhibited from fogging and tackiness and is excellent in mechanical strength and heat aging resistance. The rubber composition of the invention comprises an ethylene/?-olefin/non-conjugated polyene copolymer (A), and a polyolefin resin (B) having Mn of not less than 10,000 and/or an ethylene/?-olefin copolymer (C) having Mn of 2500 to 5000, and satisfies the following requirements: (1) a maximum value and a minimum value of an ethylene distribution parameter P of the component (A) have a relationship of Pmax/Pmin?1.

Abstract: The present invention provides a copolymer rubber which contains only small amounts of impurities and is excellent in kneading processability, extrusion processability and retention of shape and a rubber composition containing the copolymer rubber, and further provides a rubber molded product which is obtained from the rubber composition, is excellent in surface appearance, strength properties, heat aging resistance and weathering resistance and has a low compression set. The copolymer rubber of the present invention comprises structural units derived from [A]ethylene, [B] an ?-olefin of 3 to 20 carbon atoms, [C] a non-conjugated polyene having one double bond between adjacent carbon atoms in one molecule, said double bond being capable of polymerization by a metallocene catalyst, and [D] a non-conjugated polyene having two of the above double bonds in one molecule, and the copolymer rubber satisfies specific requirements (1) to (5).

Abstract: An object of the present invention is to provide an olefin-based thermoplastic elastomer composition that has both weatherability and flexibility at low temperatures, is excellent in fluidity, and causes no stickiness even in the use at high temperatures; a process oil composition for elastomers that serves as the raw material of the thermoplastic elastomer composition and contributes to the above characteristics; and an oil-extended elastomer containing the process oil composition. The process oil composition for elastomers of the present invention has a property that, when 20 parts by weight of the process oil composition for elastomers are blended with respect to 100 parts by weight of a propylene homopolymer, the melting point of the propylene homopolymer is lowered by 2 to 4.5° C. compared to that of the propylene homopolymer without blending.

Abstract: Provided is a rubber composition which can give a tire excellent in braking performance and fuel consumption and which is excellent in mechanical strength and fatigue resistance, and a use thereof. The rubber composition of the present invention contains a (A) 60 to 0.1 parts by weight of a nonconjugated polyene copolymer, which is a random copolymer containing 96 to 70 mol % of the structural units derived from ?-olefin (A1) and 4 to 30 mol % of the structural units derived from a nonconjugated polyene (A2), and has a glass transition temperature (Tg) of ?25 to 20° C., (B) 40 to 99.9 parts by weight of a diene rubber and (C) at least one selected from the group consisting of specific polymers.

Abstract: Disclosed are a conjugated polyene copolymer comprising a random copolymer having structural units derived from ?-olefin (A1) of 2 to 20 carbon atoms and structural units derived from nonconjugated polyene (A2), said nonconjugated polyene copolymer having a glass transition temperature (Tg) of ?25 to 20 ? and Mooney viscosity of [ML(1+4)100?] of 5 to 190; a rubber composition comprising the nonconjugated polyene copolymer and a diene-based rubber (B); a modifier for tires comprising the copolymer; a rubber material for tires comprising the rubber composition; a tire tread obtained from the rubber material for tires; and a tire having the tire tread.

Abstract: A process for producing a rubber composition containing a nonconjugated polyene copolymer (A), a softener (B) and a diene rubber (C), comprising: a step of mixing a copolymer composition (I), said copolymer composition (I) comprising 100 parts by weight of a nonconjugated polyene copolymer (A), said nonconjugated polyene copolymer (A) being a random copolymer containing 96 to 70 mol % of the structural units derived from ?-olefin (A1) and 4 to 30 mol % of the structural units derived from nonconjugated polyene (A2) and having a glass transition temperature (Tg) of ?25 to 20° C., and 1 to 100 parts by weight of the softener (B); the diene rubber (C); and optionally further the softener (B). A tire tread using the rubber composition and a tire having the tire tread.

Abstract: A tire provided with a tire tread made from a rubber composition comprising (A) a random copolymer based on non-conjugated cyclic polyene comprising structural units originated from one or more &agr;-olefins (A1) and originated from one or more non-conjugated cyclic polyene (A2), the said random copolymer having a content of the structural unit(s) originated from one or more &agr;-olefins (A1) in the range of 93 to 70 mole %; a content of the structural unit originated from one or more non-conjugated cyclic polyene (A2) in the range of 7 to 30 mole %; an intrinsic viscosity [&eegr;], determined in decalin at 135° C., in the range of 0.01 to 20 dl/g; a glass transition temperature (Tg) of not higher than 40° C.; and an iodine value in the range of 50 to 150, and (B) a rubber based on diene, in a weight proportion of {the random copolymer based on non-conjugated cyclic polyene (A)} versus {the rubber based on diene (B)} in the range from 60/40 to 0.1/99.

Abstract: The ethylenic copolymer rubber according to the present invention is a novel and useful ethylenic copolymer rubber which can be cross-linked at a high velocity and is superior in scorching stability, in workability and in moldability, of which cross-linked product is superior in the mechanical properties, such as the cross-linked rubber strength etc., and in the form-preservability. A cross-linkable rubber composition containing this ethylenic copolymer rubber is utilized for producing, for example, cross-linked molded rubber product for use as sealing element and automobile weather strip sponge.