Verfahren zur Herstellung von gegen Gefrieren und Wiederauftauen bestaendigen,zur Verwendung in UEberzugsmitteln geeigneten waessrigen Aminoester-Polymerisatdispersionen

摘要

Aqueous amino-ester polymer latices comprise an aqueous dispersion of the product obtained by reacting a vinyl addition polymer containing 0.3 to 5% by weight of unsaturated carboxylic acid units with an aziridine of the formula where R1 is H, C1-C5 alkyl or benzyl, R2 and R3 which may be the same or different are H, C1-C5 alkyl, benzyl or aryl and R4 is H or C1-C5 alkyl, the aziridine being reacted with the polymer in an amount stoichiometrically equivalent to 10 to 70% of the total pendent carboxyl groups in the polymer, the dispersion having a pH of 7 to 10 and containing 0.3 to 10%, by weight of the polymer, of at least one non-ionic surfactant. The acid polymer comprises units of an acid monomer such as acrylic, methacrylic, crotonic or itaconic acid or maleic anhydride and units of one or more comonomers having 2 to 20 carbon atoms, e.g. alkyl acrylates and methacrylates, conjugated dienes, e.g. butadiene, olefins, e.g. ethylene, acrylonitrile, styrene and its alkyl derivatives, vinyl acetate and dibutyl maleate. Aziridines specified are ethyleneimine and propyleneimine. Suitable non-ionic surfactants include alkyl phenoxy polyethoxy ethanols, polyethoxy-ethanol derivatives of methylene-linked alkylphenols, and ethoxylated mercaptans, thiophenols, fatty acids, fatty alcohols and etherified or esterified polyhydroxy compounds. The iminated polymer latices are useful as coating compositions and adhesives and may include additives such as methyl cellulose polyacrylic acid, tributyl phosphate, potassium tripoly-phosphate, waxes, ethylene glycol, water-soluble gums, dihydroxy-benzophenone, borax, phenyl mercury oleate, talc, mica, titanium dioxide, Carbitol (Trade Mark), xylene, diacetone alcohol and benzyl butyl phthalate. In the Examples the carboxylic polymers are generally prepared by emulsion polymerization using redox catalysts comprising potassium or ammonium persulphate and/or hydrogen peroxide in combination with sodium bisulphite or metabisulphite and possibly ferrous ammonium sulphate; and where ethylene is a comonomer, by continuous polymerization under pressure in the presence of benzene using t-butyl persulphate catalyst.ALSO:Coating compositions, e.g. paints, suitable for application to surfaces such as wood, concrete, walls, clapboard siding and metals, e.g. aluminium and chromium, comprise aqueous polymer latices of carboxylic vinyl addition polymers which have been reacted with an aziridine compound to convert 10 to 70% of the carboxylic groups to amino-ester groups (see Division C3), the latex having a pH of 7 to 10 and containing 0.3 to 10%, by weight of the polymer, of at least one non-ionic surfactant. Carboxylic polymers specified are copolymers of methacrylic or crotonic acid with one or more monomers selected from methyl methacrylate, 2-ethylhexyl acrylate, ethyl acrylate, styrene, butyl acrylate, vinyl acetate, dibutyl maleate, butadiene, butyl methacrylate, acrylonitrile and ethylene. Optional additives include pigments, extenders, organic solvents, bodying agents, defoaming agents, humectants and bactericides or fungicides; specified are talc, mica, titanium dioxide, Carbitol (Trade Mark), xylene, diacetone alcohol, benzyl butyl phthalate, methyl cellulose, polyacrylic acid, tributyl phosphate, potassium tripolyphosphate, waxes, ethylene glycol, water-soluble gums, dihydroxy benzophenone, borax and phenyl mercury oleate. The compositions may be applied to the substrate by brushing.