| abstract |
【Task】 Disclosed is a nitrile group-containing highly saturated copolymer rubber which has good normal-state properties and can give a crosslinked product particularly excellent in compression set resistance. [Solution] α, β-ethylenically unsaturated nitrile monomer unit (a) 10.0-40.0% by weight, α, β-ethylenically unsaturated dicarboxylic acid monoester monomer unit (b) 5.5-10 0.0% by weight, (meth) acrylic acid alkoxyalkyl ester monomer unit having 2 to 8 carbon atoms of alkoxyalkyl group (c) 11.0 to 30.0% by weight, and conjugated diene monomer unit (d Nitrile group-containing highly saturated copolymer rubber having 20.0 to 73.5% by weight and formed by hydrogenating at least a part of the conjugated diene monomer unit (d). [Selection figure] None |