GB776278A - Improvements relating to the modification of polymeric materials - Google Patents

Abstract

The tendency of thermoplastic polymeric materials derived from ethylenically-unsaturated hydrocarbons or their halo-substituted derivatives to accumulate electrostatic charges is reduced by incorporating a synthetic polyelectrolyte containing free carboxyl groups or neutralized carboxyl groups in salt form. The polymeric material may be polyethylene, polystyrene or polyvinyl chloride. The polyelectrolytes may be polymers or copolymers of acrylic or methacrylic acids or their alkali or alkaline earth metal salts; copolymers of these with vinyl acetate, vinyl alcohol, vinyl alkyl ethers, styrene, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, alkyl esters of acrylic or methacrylic acid or vinyl chloride; copolymers of maleic acid or a derivative of maleic acid containing one free carboxyl group, e.g. maleamic acid or alkyl half-esters of maleic acid in which the alkyl group contains 1 to 4 carbon atoms, or their salts with vinyl acetate, vinyl alcohol, vinyl alkyl ethers, styrene, isobutylene, acrylic or methacrylic acids or their esters or vinyl chloride; or suitably aftertreated polymers, e.g. hydrolysed polymers or copolymers of acrylonitrile or vinylacetatemaleic anhydride copolymers. The modified polymeric material may be prepared by polymerization in the presence of the polyelectrolyte or by milling with the polyelectrolyte. Dyes, pigments, plasticizers and lubricants, e.g. dioctyl phthalate, chlorinated diphenyl and lead stearate, and natural or synthetic resins may be added, and the compositions moulded or extruded. Specification 768,662, [Group III], is referred to.