GB848350A - Compositions comprising a thermoplastic acrylic copolymer and a diglycidyl ether - Google Patents

Abstract

A composition comprises an aqueous dispersion of (A) 40 to 95 parts by weight of a water-insoluble linear thermoplastic copolymer of 1 to 10 mole per cent of acrylic, methacrylic, itaconic, maleic or fumaric acid or an ammonium or manoamine salt thereof and 90 to 99 mole per cent of at least one of styrene, vinyl acetate or neutral alkyl, preferably C1-C18 alkyl, esters of one of the above acids and (B) 5 to 60 parts by weight of a water-soluble or readily water-dispersible aliphatic diglycidyl ether having one of the following formulae : <FORM:0848350/IV(a)/1> where R is a C2-Cb alkylene group, <FORM:0848350/IV(a)/2> where X is a number having an average value of 1 to 3, and <FORM:0848350/IV(a)/3> where m is an integer of 2 to 4 and z is a number having an average value of 1 to 5, i.e. diglycidyl ethers of alkylene glycols and glycerol, the sum of the parts by weight of (A) and (B) being 100. Copolymers (A) specified are a methyl methacrylate/ethyl acrylate/methacrylic acid terpolymer, a methyl methacrylate/n-butyl acrylate/acrylic acid terpolymer and a methyl methacrylate/ethyl acrylate/acrylic acid terpolymer. The compositions may also contain pigments such as titanium dioxide, copper phthalocyanine, ultramarine, zinc oxide, sulphide and chromate, barium sulphate, calcium carbonate and carbon black. The compositions are used in the production of coatings which may be cured by co-reaction between the ingredients to an infusible and insoluble state by heating to 200 DEG to 400 DEG F ; preferably in the presence, as a catalyst, of an amine, specified amines being methylamines, ethylamines, pyridine, benzylamine, benzyl dimethylamine, ethylene diamine, diethylene triamine, triethylene tetra-amine, lutidines, collidines, 1,8-diamino-p-menthane, N,N,N1,N1-tetramethyl-1,8-diamino-p-menthane, and N,N1-dimethyl-1,8-diamino-p-menthane.ALSO:Surfaces of glass, porcelain and metals such as iron, steel, copper, brass, aluminium, chromium and nickel are coated by applying thereto a composition comprising an aqueous dispersion of (A) 40 to 95 parts of a waterinsoluble linear thermoplastic copolymer of 1 to 10 mole per cent of acrylic, methacrylic, itaconic, maleic or fumaric acid or an ammonium or amine salt thereof and 90 to 99 mole per cent of at least one of styrene, vinyl acetate or neutral esters of one of the above acids and (B) 5 to 60 parts of a watersoluble or readily water-dispersible aliphatic diglycidyl ether (see Group IV(a)). After drying the coatings are heated to cure them to an infusible and insoluble state. The compositions may also include pigments such as titanium dioxide, ultramarine zinc oxide, sulphide and chromate, barium sulphate, calcium carbonate, carbon black and copper phthalocyanine.