GB1057723A - Polymeric thickening agents - Google Patents

Abstract

Novel water-soluble copolymer salts are prepared by polymerizing in aqueous emulsion an N-alkoxyalkyl or N-cycloalkoxyalkyl derivative of an ethylenically unsaturated amide and an a ,b -ethylenically unsaturated carboxylic acid, and reacting the product with a basic substance, e.g. an alkali metal or ammonium hydroxide, or an organic base, e.g. diethylamine, morpholine, hydrazine or dimethylaminoethanol. The amide monomer is suitably a compound of the formula <FORM:1057723/C3/1> in which R is an alkyl or cycloalkyl radical having up to twelve carbon atoms and R1 is hydrogen, chlorine or a cyano or alkyl radical. Acid comonomers specified are acrylic acid, methacrylic acid, itaconic acid, maleic acid and fumaric acid; derivatives of suitable polycarboxylic acids, e.g. partial esters, having at least one free carboxylic acid group may also be used. Other monomers may additionally be used, e.g. styrene, vinyl toluene, methyl methacrylate, ethyl acrylate, di-n-butyl itaconate, di-n-butyl maleate, di-n-octyl maleate, acrylonitrile, 2-hydroxyethyl methacrylate, 2-hydroxy propyl methacrylate, divinylbenzene, glycol dimethacrylate and methylene-bis-acrylamide. In examples, N-n-butoxy methylacrylamide, ethyl acrylate, methyl methacrylate and methacrylic acid are emulsion polymerized using ammonium persulphate catalyst, sodium N-methyl-N-oleoyl-taurate emulsifier and lauryl mercaptan modifier, part of the components being added during the course of polymerization, and the product is neutralized with ammonia or dimethylamino-ethanol. The water-soluble copolymer salts can be rendered insoluble by curing and are suitable as thickening agents in coating compositions and textile-treating compositions. In the examples, such compositions include the following ingredients: red iron oxide, barytes, talc, tri-n-butyl phosphate, ethylene glycol mono-n-butyl ether, titanium dioxide, isophorone, calcium carbonate, methyl cellulose, polyacrylic acid (Trade Mark Primal ), polyvinyl acetate, ammonium chloride and a styrene-n-butyl acrylate - N - cyclohexyloxymethyl - acrylamide copolymer. Reference has been directed by the Comptroller to Specification 792,874.ALSO:Compositions suitable for coating steel, aluminium and asbestos (e.g. priming and lacquer compositions) and for application to textiles, e.g. cotton fabric, comprise as thickener a water-soluble inorganic (e.g. alkali metal or ammonium) or organic base salt of a copolymer comprising as essential components units of an N-alkoxy alkyl or N-cyclo-alkoxy alkyl deravative of an ethylenically unsaturated amide and units of an a , b -ethylenically unsaturated carboxylic acid. The thickener can be cured to a water-insoluble form. Exemplified thickeners are the ammonium and dimethyl-aminoethanol salts of a copolymer of N-n-butoxymethylacrylamide, ethyl acrylate, methyl methacrylate and methacrylic acid. Other ingredients included in the coating compositions illustrated are red iron oxide, barytes, talc, tri-n-butyl phosphate, ethylene glycol mono-n-butyl ether, titanium dioxide, isophorone, calcium carbonate, methylcellulose, polyacrylic acid (Trade Mark "Primal"), polyvinyl acetate, ammonium chloride and a styrene-n-butyl acrylate-N-cyclohexyloxymethyl-acrylamide copolymer. Reference has been directed by the Comptroller to Specification 792,874.