| 摘要 |
PROBLEM TO BE SOLVED: To provide an unsaturated nitrile-conjugated diene copolymer rubber that can prepare a low-viscosity compound solution suitable for production of blanket without extreme reduction of polymer concentration and a rubber composition containing said copolymer rubber as a rubber component. SOLUTION: The objective unsaturated nitrile-conjugated diene copolymer is a random copolymer comprising 10-45 wt.% of unsaturated nitrile units as acrylonitrile and 90-55 wt.% of conjugated diene units as butadiene and has the number-average molecular weight of 50,000-150,000 according to the GPC in which the proportion of the component with a molecular weight of <=50,000 is 15-25 wt.% in the copolymer, while the proportion of the copolymer with a molecular weight of >=2,000,000 is 5-15 wt.%. |
