Nitrile copolymer rubber cross-linked product, nitrile copolymer rubber composition, and method for producing the composition

摘要

It contains 0.1 to 100 parts by weight of a plasticizer (B) with respect to 100 parts by weight of a nitrile copolymer rubber (A) having 55 to 80% by weight of α, β-ethylenically unsaturated nitrile monomer units. A nitrile copolymer rubber cross-linked product having an embrittlement temperature of -50 to -5 ° C. Preferably, the gasoline permeability coefficient of gasohol having a weight ratio of isooctane / toluene / ethanol of 40/40/20 is 200 g · mm / m 2 · day or less, and preferably, the plasticizer (B) is a specific dicarboxylic acid. It is an ester compound of an acid compound and an ether bond-containing alcohol. According to the present invention, although the content of unsaturated nitrile monomer units is extremely high, the nitrile copolymer has a low embrittlement temperature (excellent cold resistance) and low gasoline permeability resistance (excellent gasoline permeability resistance). A polymer rubber cross-linked product can be provided.