Aqueous dispersions of self-crosslinking copolymers

摘要

Copolymers are made by copolymerizing in aqueous dispersion with the use of a non-ionic emulsifier a mixture of (1) 0,5 to 10% by weight of an olefinically unsaturated monomer having a hydrophilic group, e.g. a carboxylic, hydroxy, carbonamide, sulphonic acid or polyglycol ether group, (2) 0,5 to 15% by weight of a monomer of the formula: in which R represents H or CH3, R1 represents H or an alkyl, aralkyl or aryl group, and A represents a radical of the formula in which R2 represents an alkyl or cycloalkyl radical and R3 and R4 each represent an alkyl, cycloalkyl, aralkyl or aryl radical, or together with the nitrogen atom to which they are attached represent a heterocyclic radical, and (3) 75 to 99% by weight of further olefinically unsaturated monomers which are free from hydrophilic groups and from the self-cross-linking groups of the monomers (2). Monomers (1) specified are acrylic and methacrylic acids and monoesters thereof with polyhydric alcohols and polyglycol ethers, maleic acid and monoesters, e.g. monobutyl, thereof, allyl monoethers of polyhydric alcohols and polyglycol ethers, acrylamide, methacrylamide, vinyl sulphonic acid and styrene sulphonic acid, and also compounds which contain hydrophilic groups after saponification, e.g. vinyl acetate and propionate and maleic anhydride. Monomers (2) specified are ethers of methylol acrylamide and methacrylamide and Mannich bases of acrylic and methacrylic acid, particularly those disclosed in Specification 898,967. Monomers (3) specified are C1-C20 aliphatic and cycloaliphatic esters of acrylic and methacrylic acids, styrene, vinyl toluene, ar-halogenated styrenes, acrylonitrile, methacrylonitrile, vinyl and vinylidene chlorides, vinyl acetate and propionate, monovinyl ethers, butadiene, isoprene, chloroprene and cross-linking monomers such as glycol diacrylates and dimethacrylates, allyl acrylate and methacrylate and divinyl benzene. Non-ionic emulsifiers specified are condensation products of ethylene oxide with long-chain fatty alcohols, acids and amides, and esters of long-chain monocarboxylic acids with sugars. Also present may be ionic emulsifiers, e.g. long-chain sulphates and sulphonates. The polymerization is preferably carried out in an acid medium with the aid of a redox catalyst, such as combinations of persulphates and pyrosulphites or bisulphites. Catalyst and monomer may be added to the reaction system during the course of polymerization. Also present during polymerization may be mercaptans. After completion of polymerization the pH of the resulting dispersion is preferably raised to between 6,5 and 9. The copolymers may be cross-linked by heating and/or by the action of acids or acid yielding substances. The dispersions of the copolymers may be used for treating textiles for which purpose they may have added thereto water-soluble condensates of aldehydes, e.g. formaldehyde, with urea, dicyandiamide, melamine and phenols and alkylmethylol derivatives thereof; thickeners, e.g. tragacanth, starch, cellulose ethers, sodium alginate, polyvinyl alcohol, polyacrylamide and polyacrylic acid salts; emulsions of benzine in water, phthalocyanine dyes, azodyestuffs, metal oxides, e.g. titanium dioxide, and carbon black. Specification 792,874 also is referred to.ALSO:Textiles, e.g. those made from cotton or rayon, are printed, padded or impreganted with an aqueous dispersion comprising a non-ionic emulsifying agent and a copolymer of (1) 0.5% to 10% by weight of an olefinically unsaturated monomer having a hydrophilic group, e.g. unsaturated carboxylic and sulphonic acids, amides or alcohols, (2) 0.5% to 15% by weight of a methylol ether of acrylamide or methacrylamide or a Mannich base of acrylic or methacrylic acid, and (3) 75% to 99% by weight of further olefinically unsaturated monomers which are free from hydrophilic groups and from the self-cross-linking groups of monomers (2), e.g. acrylic and methacrylic esters and nitriles, vinyl aromatic compounds, vinyl esters, vinyl ethers, vinyl and vinylidene chlorides, conjugated dienes and monomers containing a plurality of unsaturated groupings. Non-ionic emulsifiers specified are condensation products of ethylene oxide with long chain fatty alcohols, acids and amides, and esters of long chain monocarboxylic acids, with sugars. Also present in the aqueous dispersions may be ionic emulsifiers, e.g. long chain sulphates and sulphonates; water-soluble condensates of aldehydes with urea, dicyandiamide, melamine and phenols and alkoxymethyl derivatives thereof; thickeners, e.g. tragacanth, starch, cellulose ethers, sodium alginate, polyvinyl alcohol, polyacrylamide and polyacrylic acid salts; emulsions of benzine in water, and colouring matter, e.g. phthalocyanine dyes, azo-dyestuffs, metal oxides, such as titanium dioxide, and carbon black. After application to the textiles the polymers in the dispersions are cross-linked by the action of heat and/or acid reacting substances. Specifications 792,874 and 898,967 are referred to.