Rubber compositions and vulcanized rubber compositions

A rubber composition comprising 30 to 95 parts by weight of the following component (a) and 70 to 5 parts by weight of the following component (B) and 1 to 10 parts by weight of the following component (C) per 100 parts by weight of the total amount of the components (A) and (B), wherein component (A) and component (B) total 100 parts by weight:

• component (A) is (1) an ethylene-acrylate or ethylenemethacrylate copolymer rubber, (2) ethylene-acrylate-unsaturated glycidyl ester copolymer rubber or ethylene-methacrylate-unsaturated glycidyl ester copolymer, or (3)ethylene-acrylate-unsaturated glycidyl ether or ethylene-methacrylate-unsaturated glycidyl ether copolymer, wherein the amount ratio in moles of ethylene and acrylate or methacrylate in (1), (2) and (3) is in the range from 50:50 to 85:15;
• component (B) is an epichlorohydrin rubber which is vulcanizable with an organic peroxide and has unsaturated carbon-carbon double bonds as a vulcanizable group in the amount of 1 to 15 mole % in the rubber;
• and
• component (C) is an epoxy resin obtained by condensation reaction of bisphenol A and epichlorohydrin, said epoxy resin having a weight-average molecular weight in the range of 100 to 15,000 and an epoxy equivalent weight in the range of 100 to 10,000 containing an epoxy ring.