Impact strength, stress-whitening and bruise-resistance for impact modified polypropylene

摘要

The present invention relates to a process for preparing high melt flow rate thermoplastic compositions that have improved impact and bruise-resistance properties and to the thermoplastic composition that are produced by the process of the instant invention. Specifically, the process comprises the steps of precontacting a non-crosslinked elastomeric polymeric component with a peroxide compound at a temperature below the decomposition temperature of the peroxide and below the melting point of the non-crosslinked polymeric component to produce a peroxide adsorbed polymeric component; and melt mixing the aforementioned peroxide adsorbed polymeric component with a high propylene content polymeric component selected from the group consisting of homopolymers of propylene, block copolymers of propylene and ethylene, and thermoplastic olefin polymers at a temperature above the decomposition temperature of the peroxide.