CONTROLLED CRACKING OF ALPHA-OLEFIN POLYMERS

摘要

An improved process for the controlled reduction of average molecular weight and alteration of molecular weight distribution of C3-C8 alpha-monoolefin homopolymers or copolymers comprises adding a peroxide continuously at a programmed cyclic rate to the polymer or copolymer and heating the mixture in a melt extruder. The rate of peroxide addition is varied at a frequency with a period longer than the decomposition time of the peroxide but shorter than the passage time of the mixture through the extruder, so as to achieve combinations of melt flow and molecular weight distribution for the polymer not possible with prior art steady rates of addition.