| 摘要 |
　Provided is a nitrile copolymer rubber obtained by emulsion polymerization using 2,2,4,6,6-pentamethylheptane-4-thiol as a chain transfer agent, the pH of the polymer being 8.5 or below. The pH of the polymer is preferably 8.0 or below. According to the present invention, there can be provided a nitrile copolymer rubber which gives a crosslinked rubber of excellent heat resistance and resistance to compression permanent strain. |
