A nitrile group-containing copolymer rubber containing α,β-ethylenically unsaturated nitrile monomer units in a ratio of 10 to 60 wt% and having a Z-average radius of gyration of 100 nm or more is provided. Preferably, the nitrile group-containing copolymer rubber of the present invention has an iodine value of 120 or less. Further, preferably, the nitrile group-containing copolymer rubber of the present invention has a plasticity number of 14 to 90. According to the present invention, it is possible to provide a nitrile group-containing copolymer rubber able to give a cross-linked rubber excellent in tensile stress, compression set resistance, and low heat buildup property.
本发明提供了一种含腈基团的共聚橡胶,它含有α,β-
乙烯基不饱和腈单体单元,其比例为 10 至 60 wt%,Z 平均回转半径为 100 nm 或更大。优选地,本发明的含腈基共聚橡胶的
碘值为 120 或更低。此外,优选地,本发明的含腈基共聚橡胶的塑性数为 14 至 90。根据本发明,可以提供一种含腈基团的共聚橡胶,该橡胶能够提供一种在拉伸应力、抗压缩永久变形和低热积聚特性方面性能优异的交联橡胶。