GB1006779A - Resin compositions - Google Patents

Abstract

A composition comprises (a) at least 50 parts by weight of an interpolymer of a monomer mixture consisting of (1) 2-30% by weight of at least one acid monomer of the formula: <FORM:1006779/C3/1> where R is hydrogen, a halogen atom or an alkyl group containing 1 to 4 carbon atoms, (2) 2-40% by weight of a nitrile monomer selected from acrylonitrile, methacrylonitrile and mixtures thereof, and (3) the balance at least one ethylenically unsaturated monomer interpolymerizable with said acid monomer and said nitrile monomer, and (b) less than 50 parts by weight of an epoxy compound containing a plurality of epoxy groups of the structure: <FORM:1006779/C3/2> said component (b) being present in an amount sufficient to provide an average of at least 0.4 epoxy group per carboxyl group of component (a). Monomer (1) is preferably acrylic or methacrylic acid and monomer (3) is exemplified by one or more of styrene, methyl methacrylate, ethyl acrylate, vinyl butyl ether, and vinyl methyl ketone. Epoxy compounds exemplified are an epichlorohydrin bisphenol A condensate, the diglycidyl ether of bisphenol A, the triglycidyl ether of glycerine, and the diglycidyl ether of ethylene glycol. The compositions are preferably used in the form of solutions in organic solvents, although a moulding powder comprising 50 parts of wood flour, 10 parts of epoxy compound, and 50 parts of acrylic acid terpolymer is exemplified. Other ingredients such as titanium dioxide and etherified amino-plast resins may be included. The acrylic acid terpolymer is preferably made by a process which comprises adding a mixture of the said monomers to an organic solvent maintained at a temperature of at least 80 DEG C. in the presence of at least 0.25% by weight (calculated on the total weight of monomers) of a monomer-soluble free-radical-generating catalyst, the rate of addition of the said monomers being such that the monomers are polymerized at substantially the rate at which they are being added to the solvent. Specified initiators are tertiary butyl perbenzoate ditertiary butyl peroxide and benzoyl peroxide. Polymerization may take place in the presence of sulphur dioxide or a diene sulphone.ALSO:Metal surfaces, particularly phosphatized or untreated steel panels, paper, cardboard, leather, glass, porcelain &c. may be coated with, or webs of paper or fabric, particularly glass fibre fabric, may be impregnated with a composition comprising (a) at least 50 parts by weight of an interpolymer of a monomer mixture consisting of (1) 2-30% by weight of at least one acid monomer of the formula: <FORM:1006779/B1-B2/1> where R is hydrogen, a halogen atom or an alkyl group containing 1-4 carbon atoms, (2) 2-40% by weight of a nitrile monomer selected from acrylonitrile, methacrylonitrile or mixtures thereof, and (3) the balance at least one ethylenically unsaturated monomer interpolymerizable with said acid monomer and said nitrile monomer, and (b) less than 50 parts by weight of an epoxy compound containing a plurality of epoxy groups of the structure: <FORM:1006779/B1-B2/2> said component (b) being present in an amount sufficient to provide an average of at least 0,4 epoxy group per carboxyl group of component (a). Monomer (1) is preferably acrylic or methacrylic acid and monomer (3) is exemplified by one or more of styrene, methyl methacrylate, ethyl acrylate, vinyl butyl ether, and vinyl methyl ketone. The compositions are preferably sprayed on to the substrate in the form of solutions in conventional organic solvents. Fillers and pigments such as titanium dioxide may be present.