COPOLYMER RUBBER, RUBBER COMPOSITION, AND MOLDED RUBBER

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).