Patent ID: 6469100
Filing Date: 2002-10-22
Classification: C08F,C08L,Y10S

Abstract:
A block copolymer comprising one or more blocks of a polymer made of a polypropylene (hereinafter referred to as â€œPP blockâ€ ) and one or more blocks of a polymer made of an ethylene-propylene copolymer (hereinafter referred to as â€œEPR blockâ€ ) connected to each other, wherein the block copolymer and each of said blocks have the following properties (1) to (7):(1) the thickness of the interface of PP block with EPR block in the dispersion structure of the block copolymer is from 20 nm to 1,000 nm; (2) the weight-average molecular weight of the polypropylene in PP block (hereinafter referred to as â€œMW.PPâ€ ) is from 10,000 to 1,000,000; (3) the proportion of mesopentad chain in the polypropylene in PP block is not less than 95%; (4) the particle diameter of the disperse phase of the ethylene-propylene copolymer in EPR block is from not less than 0.2 &mgr;m to not more than 3 &mgr;m as calculated in terms of weight-average area; (5) the weight-average molecular weight of the ethylene-propylene copolymer in EPR block (hereinafter referred to as â€œMW.Râ€ ) is from 50,000 to 1,000,000; (6) the propylene content in the ethylene-propylene copolymer with EPR block is from 20 mol-% to 80 mol-%; and (7) the composition fluctuation in molecular weight of the ethylene-propylene copolymer in EPR block is within Â±5% from the average composition.