Propylene block copolymer composition for production of transparent moulded products, e.g. for cars, contains two statistical propylene-ethylene copolymers with specified inherent viscosity relationships

摘要

Propylene block copolymer compositions of two statistical propylene/ alpha -olefin copolymers (A and B) containing 99.4-99.9 and 35-60 mol% propylene respectively, in which the alpha -olefin in (A) is ethylene and/or 1-butene, the inherent viscosity (iv) of (B) is 0.5-2.0 dl/g, the ratio of (iv-B)/(iv-A) = 0.3-1.2 and the product of this ratio and the wt. ratio (A/B) = 1.0-3.0.