Patent ID: 8586674
Filing Date: 2013-11-19
Classification: C08K,C08L

Abstract:
1. A method for producing a copolymer rubber composition comprising: a copolymer rubber (1); and a copolymer rubber (2), as a rubber component, wherein the content of the copolymer rubber (1) is 60% by weight or more and 75% by weight or less, and the content of the copolymer rubber (2) is 40% by weight or less and 25% by weight or more, based on 100% by weight of the total of the copolymer rubber (1) and the copolymer rubber (2); and the difference in iodine value between the copolymer rubber (1) and the copolymer rubber (2) is 5 or more and 30 or less, and wherein, the copolymer rubber (1) is an ethylene-α-olefin-nonconjugated polyene copolymer rubber wherein the content of a monomer unit based on ethylene is 50 mol % or more and 70 mol % or less; the content of a monomer unit based on α-olefin is 50 mol % or less and 30 mol % or more (provided that the total of the monomer unit based on ethylene and the monomer unit based on α-olefin is 100 mol %); and the iodine value is 10 or more and 30 or less, and the copolymer rubber (2) is an ethylene-α-olefinic copolymer rubber wherein the content of a monomer unit based on ethylene is more than 70 mol % and 95 mol % or less; the content of a monomer unit based on α-olefin is less than 30 mol % and 5 mol % or more (provided that the total of the monomer unit based on ethylene and the monomer unit based on α-olefin is 100 mol %); and the iodine value is 0 or more and 8 or less, which method comprises manufacturing one of the copolymer rubber (1) and the copolymer rubber (2) in a first reaction tank, feeding the one copolymer rubber manufactured in the first reaction tank to a second reaction tank, and manufacturing the other copolymer rubber in the second reaction tank in the presence of the one copolymer rubber, wherein the two tanks are coupled in series; and wherein the polymerization catalysts used in manufacturing of the copolymer rubber (1) are those containing a vanadium compound selected from the group consisting of VO(OC and wherein the polymerization catalyst used in manufacturing of the copolymer rubber (2) are those having a vanadium compound selected from the group consisting of VO(O(iso-C