Graft copolymers, process for their preparation, process employing them to improve polyolefins and mixtures and products containing them with polyolefins especially for improving the mutual compatibility of polymers

摘要

Graft copolymers comprising a nonpolar polyolefin backbone which preferably has a relatively high weight average molecular weight on which at least one polymethacrylate chain is grafted, which is prepared by dissolving a nonpolar polyolefin in an inert hydrocarbon solvent and, with stirring of the mixture, addition of methacrylate monomer with an initiator to produce a low constant flow of radicals in order to graft a polymer chain by covalency onto the polyolefin backbone. The graft copolymer can be mixed with a polyolefin matrix to improve its physical properties, especially to ensure a good balance of the tensile modulus, of flexural strength and of melt viscosity, and also to improve the compatibility of polymers of different polarities.