US 9,809,704 B2
Rubber composition and molded article
Tetsuji Takezawa, Ichihara (JP); and Sadayuki Nakano, Ichihara (JP)
Assigned to SUMITOMO CHEMICAL COMPANY, LIMITED, Tokyo (JP)
Appl. No. 15/105,878
Filed by Sumitomo Chemical Company, Limited, Tokyo (JP)
PCT Filed Dec. 18, 2014, PCT No. PCT/JP2014/084447
§ 371(c)(1), (2) Date Jun. 17, 2016,
PCT Pub. No. WO2015/093622, PCT Pub. Date Jun. 25, 2015.
Claims priority of application No. 2013-263415 (JP), filed on Dec. 20, 2013.
Prior Publication US 2016/0304710 A1, Oct. 20, 2016
Int. Cl. C08L 23/16 (2006.01); C08F 210/18 (2006.01); C08K 5/14 (2006.01)
CPC C08L 23/16 (2013.01) [C08F 210/18 (2013.01); C08K 5/14 (2013.01)] 4 Claims
 
1. A rubber composition comprising the following component (A),
the following component (B), and the following component (C), wherein:
the component (A) is an ethylene-α-olefin-nonconjugated polyene copolymer rubber containing an ethylene unit, an α-olefin unit and a nonconjugated polyene unit, a number of carbon atoms of the α-olefin unit is 3 or more and 20 or less, a limiting viscosity measured in 135° C. tetralin is 2.8 dl/g or more and 5 dl/g or less, a content of the ethylene unit is 70 mol % or more and 90 mol % or less (where a total of the content of the ethylene unit and a content of the α-olefin unit in the component (A) is 100 mol %), and a content of the nonconjugated polyene unit is 2% by weight or more and 20% by weight or less (where a total amount of the component (A) is 100 wt % by weight);
the component (B) is an organic peroxide; and
the component (C) is a thermosetting prepolymer, wherein a molecular weight distribution (Mw/Mn) of the component (A) is 2 or more and 5 or less.