| 摘要 |
PROBLEM TO BE SOLVED: To obtain the subject rubber-like copolymer with no need of adding any elastomer ingredient, having high stiffness and impact resistance and excellent in fluidity and appearance by preparing in a specified process. SOLUTION: This copolymer is obtained by employing following steps in the presence of a catalyst including a solid catalyst component including Mg, Ti, a halogen and an electron donor and an organic aluminum compound: a propylene monopolymer or a propylene/ethylene random copolymer containing <=5% ethylene is obtained by reacting propylene or a propylene/ethylene mixture in the first step and, thereafter, the copolymer is obtained by polymerizing the propylene/ethylene mixture in the second step. The copolymer has such properties as >=10 g/10 min MFR, 50-80 wt.% polymer block obtained in the first step, 20-50 wt.% polymer block obtained in the second step and intrinsic viscosity satisfying the formula in which [η]h is the former intrinsic viscosity and [η]r is the latter intrinsic viscosity.
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