Propylene impact copolymers

摘要

A propylene impact copolymer composition, comprises (A) propylene homo/copolymer with less than 10% of ethylene, butene, hexene or octene (40-95 wt.%), and (B) a propylene copolymer containing 20-70% of ethylene, butene, hexene or octene monomers (5-60 wt.%). (B) has molecular weight of at least 100,000, a composition distribution greater than 60% and an intrinsic viscosity > 1.00 dl/g. Independent claims are also included for: (1) a reactor-produced propylene impact copolymer composition, comprising (A) with properties as previously defined, and (B) containing 30-65% of ethylene so that it has a molecular weight of at least 150,000, a molecular weight distribution of 3.5, a composition distribution greater than 65%, an intrinsic viscosity of at least 2.00 dl/g and less than 10% of crystalline portions; and (2) the production of the propylene impact copolymer, comprises polymerizing (A) in a single stage, and polymerizing (B) in another stage and in the presence of (A). Either stage uses a metallocene catalyst.