Polypropylene impact copolymers of high ethylene content

摘要

The present invention teaches propylene-ethylene copolymers of about 5 to about 50 g/10min melt flow that have a homopolymer phase and a copolymer rubber phase in which the ethylene content of the rubber is between about 75 to about 95%w. The rubber content of the copolymer ranges between about 3%w to about 60%w. The higher rubber phase crystallinity provides overall improvement in film properties and also balance of film tensile properties in the machine and transverse directions. Compared to traditional low ethylene content-rubber impact copolymers, these copolymers have significantly enhanced melting and crystallization peaks due to polyethylene-like crystallinity in the rubber phase.