GB635986A - Improvements in or relating to vinyl resin-synthetic rubber compositions and method of preparing same - Google Patents

Abstract

A stable aqueous dispersion for the production of films and coatings comprises as the dispersed phase particles of an intimate mixture of a vinyl resin prepared by emulsion polymerization of a mixture consisting mainly of vinyl and/or vinylidene chloride and a synthetic rubber prepared by emulsion polymerization of 1 part of a butadiene-1,3 hydrocarbon with from 0.1 to 2 parts of a copolymerizable unsaturated compound. The vinyl resin is preferably a copolymer of vinyl and/or vinylidene chloride with at least 10 per cent by weight of an ester of acrylic or substituted acrylic acid. Alternative copolymerizable monomers include vinyl acetate and butyrate, styrene, acrylic acid, acrylonitrile, methyl vinyl ketone, vinyl carbazole and methyl vinyl ether. The butadiene component of the synthetic rubber may be butadiene-1,3, isoprene, 2,3-dimethyl butadiene or piperylene or a mixture of these, and the other component is preferably a nitrile of an acrylic acid but may consist of vinylidene chloride, alkyl acrylates and the vinyl compounds mentioned above. The dispersion is formed by mixing the two dispersions, of like electric charge, while stirring. The pH and size of the particles of the two dispersions should preferably be of the same order. Additional ingredients which may be added include plasticizers, e.g. tricresyl phosphate and dioctyl phthalate, pigments and fillers such as carbon black, titanium dioxide and whiting; vinyl resin stabilizers, e.g. lead carbonate or silicate; synthetic rubber stabilizers, e.g. phenyl betanaphthylamine; wetting agents, proteins and other hydrophilic colloids; and vulcanizing agents, e.g. sulphur with butyl zimate or polyalkylene polyamines, or aldehyde-amine condensates. In normal films and coatings, the vinyl resin preferably constitutes 50-90 per cent of the dry polymer content. For films prepared by the coagulant dip method, the proportions are reversed. The dispersions may provide self-sustaining films and coatings on fabric (see Group VIII), paper, wood, glass, metal, rubber and other plastic materials. Specifications 633,630 and 636,535 are referred to. The Specification as open to inspection under Sect. 91 comprises also dispersions containing vinyl resins that are prepared from one or more monomers having the structure <FORM:0635986/IV (a)/1> wherein at least one of X and Y is a negative group such as chlorine, bromine, cyano, phenyl, acyl, carboxy, carbalkoxy and similar negative groups free from olefinic linkages. This subject-matter does not appear in the Specification as accepted.ALSO:A stable aqueous dispersion for the production of films and coatings comprises as the dispersed phase particles of an intimate mixture of a vinyl resin prepared by emulsion polymerization of a mixture consisting mainly of vinyl and/or vinylidene chloride and a synthetic rubber prepared by emulsion polymerisation of 1 part of a butadiene-1, 3 hydrocarbon with 0.1 to 2 parts of a copolymerizable unsaturated compound. The vinyl resin is preferably a copolymer of vinyl and/or vinylidene chloride with at least 10 per cent by weight of an ester of acrylic or substituted acrylic acid. Alternative copolymerisable monomers include vinyl acetate and butyrate, styrene, acrylic acid, acrylonitrile, methyl vinyl ketone, vinyl carbazole and methyl vinyl ether. The butadiene component of the synthetic rubber may be butadiene-1, 3, isoprene, 2, 3-dimethyl butadiene or piperylene or a mixture of these; and the other component is preferably a nitrile of an acrylic acid but may consist of vinylidene chloride, alkyl acrylates and the vinyl compounds mentioned above. The dispersion is formed by mixing the two dispersions, of like electric charge, while stirring. The pH and size of the particles should preferably be of the same order. Additional ingredients which may be added include plasticisers e.g. tricresyl phosphate and dioctyl phthalate; pigments and fillers e.g. carbon black, titanium dioxide and whiting; vinyl resin stabilizers e.g. lead carbonate or silicate; synthetic rubber stabilizers e.g. phenyl beta-naphthylamine; wetting agents, proteins and other hydrophillic colloids; and vulcanizing agents e.g. aldehyde-amine condensates or sulphur with butyl zimate or polyethylene polyamines. Generally the vinyl resin preferably constitutes 50-90 per cent of the dry polymer content. For films prepared by the coagulant dip method, the proportions are reversed. The dispersions may provide self-sustaining films and coatings on fabric (see Group VIII), paper, wood, glass, rubber, metal and other plastic materials. Specifications 633,630 and 636,535, [both in Group IV (a)], are referred to. The Specification as open to inspection under Sect. 91 comprises also dispersions containing vinyl resins that are prepared from one or more monomers having the structure <FORM:0635986/V/1> , wherein at least one of X and Y is a negative group such as chlorine, bromine, cyano, phenyl, acyl, carboxy, carbalkoxy and similar negative groups free from olefinic linkages. This subject-matter does not appear in the Specification as accepted.