PROPYLENE/ETHYLENE BLOCK COPOLYMER COMPOSITION AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To obtain a block copolymer composition which can give moldings improved in transparency, whitening resistance, etc., and having high impact resistance by performing the usual polymerization of propylene and the subsequent copolymerization of an ethylene/propylene monomer mixture in the presence of a specified A-B block copolymer comprising propylene and ethylene. SOLUTION: This composition comprises 0.01-10wt.% A-B block copolymer (C) comprising polypropylene segments (A) and ethylene/propylene random copolymer segments (B) and 99.99-90wt.% propylene (co)polymer (D). Component C contains 5-80wt.%, segments (B) having an ethylene content of 10-90wt.%. Component D comprises 60-95wt.% propylene (co)polymer and 40-5wt.% ethylene/ propylene random copolymer.