Cationic modifications of polyalkenes. Polyethers as modificators of polypropylene and polyethylene

Abstract

Carbocations generated on polypropylene (or polyethylene) chains are able to bond the polar polymer, e.g. poly(oxytetramethylene), poly(oxyethylene), poly(oxyphenylene) or polysiloxane onto the hydrocarbon chains. The copolymers polypropylene-block-poly(oxyethylene) and polypropylene-graft-poly(oxyethylene) have outstanding compatibilizating ability in a polypropylene-CaCO3 composite. The above named copolymer (2 mass %), mixed with polypropylene and surface non-treated CaCO3, produce a composite with 50% higher impact toughness, lower melt viscosity (better flow in) and better dispersion of the filler in the matrix in comparison with the standard composite consisting of the same polypropylene matrix and treated CaCO3 (calcium stearate and stearic treatment).