Patent ID: 6657006
Filing Date: 2003-12-02
Classification: B32B,C08L,C09J

Abstract:
A coextrusion binder composition comprising a polymer or a copolymer polymeric component wherein the polymeric component consists essentially of:at least one polymer (A) selected from the group consisting of A1, A2, A3, and A4, wherein the A1, A2, A3, and A4 groups are defined as follows: (A1) graft polymers resulting from the grafting of at least one grafting monomer selected from the group consisting of carboxylic acids containing ethylenic unsaturation and the corresponding ethylenically unsaturated carboxylic acid anhydrides onto (a) impact or crystal styrene homopolymers or copolymers; and optionally (b) styrene-diene elastomer block polymers or styrene-diene elastomer block polymers in the hydrogenated state, provided that (b) is not the only polymer in the mixture of (A) and optionally (B); (A2) at least one copolymer selected from the group consisting of styrene-diene elastomer block polymers and styrene-diene block polymers in the hydrogenated state mixed with at least one polymer (B1) as defined below; (A3) graft polymers resulting from the cografting of at least one grafting monomer selected from the group consisting of carboxylic acids containing ethylenic unsaturation and the corresponding ethylenically unsaturated carboxylic acid anhydrides onto a mixture: of at least one polymer selected from the group of impact or crystal styrene homopolymers and copolymers; and of at least one polymer (c) selected from the group consisting of ethylene-vinyl acetate copolymers, and ethylene-alkyl (meth)acrylate copolymers; (A4) graft polymers resulting from the cografting of at least one grafting monomer selected from the group consisting of carboxylic acids containing ethylenic unsaturation and the corresponding ethylenically unsaturated carboxylic acid anhydrides onto at least one polymer selected from the group consisting of impact or crystal styrene homopolymers and copolymers, to which at least one tackifying resin (d) has been added, these graft polymers being furthermore mixed with at least one polymer (B1) as defined below; and at least one polymer(B) selected from the group consisting of: (B1) graft polymers resulting from the grafting of at least one grafting monomer selected from the group consisting of carboxylic acids containing ethylenic unsaturation and the corresponding ethylenically unsaturated carboxylic acid anhydrides onto the polymer (c); and (B2) terpolymers comprising a first component comprising ethylene, a second component selected from the group consisting of &agr;-olefin, vinyl acetate and alkyl (meth)acrylate and a third component comprising monomers selected from the group consisting of carboxylic acids containing ethylenic unsaturation and the corresponding ethylenically unsaturated carboxylic acid anhydrides, provided that the ethylene-alkyl (meth)acrylate copolymers may not represent more than 40% by weight of the mixture subjected to the cografting in the case of a polystyrene content lower than 30% by weight if (A3) represents the major constituent of the binder composition.