| 摘要 |
PURPOSE: To obtain a vulcanizable rubber compsn. which gives a vulcanizate excellent in resistances to dynamic fatigue, thermal aging, weathering, and ozone without detriment to the characteristics inherent in diene rubbers by compounding a diene rubber with a specific rubber. CONSTITUTION: The compsn. contains an ethylene/α-olefin/nonconjugated polyene copolymer rubber and a diene rubber in a wt. ratio of (5/95)-(95/5). The copolymer rubber is obtd. by the random copolymerization in the presence of a metallocene catalyst of ethylene, a 3-20Cα-olefin, and a nonconjugated polyene having only one C-C double bond polymerizable in the presence of this catalyst, and has a molar ratio of ethylene units toα-olefin units of (40/60)-(85/15), an iodine value of 5-50, and an intrinsic viscosity (at 130 deg.C in decalin) of 1-5dl/g. The ratio of the intrinsic viscosity of the copolymer rubber to that of a linear ethylene/propylene copolymer which has the same wt. average mol.wt. as that of the copolymer rubber and an ethylene unit content of 70mol% is 0.2-0.95.
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