THERMALLY SELF-CROSSLINKING COPOLYMERS

1496867 Self - crosslinking copolymers WACKER-CHEMIE GmbH 19 March 1976 [21 March 1975 17 Nov 1975] 11156/76 Heading C3P Thermally self-crosslinking copolymers comprise units of (a) 5-50% by weight ethylene, (b) 30-87% vinyl acetate, (c) 2-10% a mono-olefinically unsaturated N-methylol compound or an ether thereof, (d) 5-20% a (meth)- aerylate ester of a saturated alcohol having up to 10 carbon atoms, (e) 0À5-3% a mono-olefinically unsaturated carboxylic acid, (f) optionally 0À001-1% a multiply olefinically unsaturated compound and (g) optionally up to 2% a further mono-olefinically unsaturated compound. Component (c) is suitably derived from acrylamide or methacrylamide; component (e) may be acrylic, methacrylic, crotonic, maleic or fumaric acid; component (f) is preferably allyl acrylate or methacrylate but may also be vinyl crotonate, a divinyl or diallyl ester, a di-(meth)acrylate ester, a bis(meth)- acrylamide or triallyl cyanurate; and component (g) may be acrylamide or vinyl sulphonic acid. The copolymers are suitably prepared by polymerization in an aqueous medium in the presence of emulsifiers and optionally also protective colloids. The copolymers form flexible films which can be crosslinked by heating, optionally in the presence of an acidic catalyst. Applications include binding non-woven fabrics, gluing or laminating textiles, and binders for adhesives and paints.