SELBSTERLOESCHENDE STYROL-MISCHPOLYMERISAT-POLYBLENDZUBEREITUNG

1426493 Grafted chloroprene rubber polyblends MONSANTO CO 29 Aug 1973 [30 Aug 1972] 40595/73 Heading C3G A polyblend is produced by mixing in the melt phase component (A) a polymer of at least one monovinylidene aromatic monomer and 0 to 45%, by weight of the polymer, of an ethylenically unsaturated nitrile and component (B) a chloroprene rubber grafted with at least one monovinylidene aromatic monomer and 0 to 45%, by weight of the aromatic monomer and nitrile, of an ethylenically unsaturated nitrile, the grafted chloroprene rubber constituting from 16À5% to 80% by weight of the polyblend and providing from 15% to 40% by weight of the polyblend of chloroprene rubber, one or more monovinylidene aromatic monomers providing chemically combined chlorine and/or bromine, the amount of such monomer providing at least 11% by weight of chlorine and/or at least 6 % by weight of bromine in the polyblend. Examples are given of polyblends comprising (a) polychloroprene grafted with chlorostyrene and poly(monochlorostyrene); (b) polychloroprene grafted with chlorostyrene and acrylonitrile and chlorostyrene/acrylonitrile copolymer; (c) polychloroprene grafted with styrene and monobromostyrene and styrene/monobromostyrene copolymer; (d) polyblend as in (c), containing in addition the polybutadiene grafted with styrene and acrylonitrile. A mixture of grafted chloroprene rubbers having different particle sizes may be used.