| 摘要 |
PROBLEM TO BE SOLVED: To obtain a seal member excellent in tensile strength, etc. by using a composition obtained by crosslinking a crystalline polyolefin resin and an ethylene/α-olefin/nonconjugated polyene copolymer rubber by dynamic heat treatment. SOLUTION: The ethylene/α-olefin/nonconjugated polyene copolymer rubber is obtained by the random copolymerization of ethylene with a 3-20C α-olefin and a nonconjugated polyene in the presence of a metallocene catalyst, comprises ethylene units and α-olefin units in a molar ratio of 40/60 to 95/5, and has an iodine value of 1-50 and an intrinsic viscosity of 1.0-10 dl/g as measured in decalin at 135 deg.C. The member is made from a composition obtained by dynamically heat-treating a thermoplastic elastomer composition comprising 90-40 pts.wt. above copolymer rubber and 10-60 pts.wt. crystalline polyolefin under conditions of the formula. In the formula, T is the resin temperature ( deg.C) at the exit of the die of an extruder; X is the diameter (mm) of the extruder screw; Y is the maximum shear rate (sec-1) exerted in the extruder; and Z is an extrusion rate (kg/h). |
