Curable adhesive compsn. e.g. for metal-plastic laminates - comprising hydroxyl-contg. acrylic! copolymer and a poly:isocyanate

摘要

Curable adhesive compsn. comprises (a) a copolymer obtd. by polymerisation of (i) 25-64.8 wt.% of one or more alkyl esters of (meth)acrylic acid with 1-8C in the alkyl gp.; (ii) 20-40 wt.% (meth)acrylonitrile and/or vinyl acetate; (iii) 15-35 wt.% one or more omega-hydroxyalkyl esters of (meth)acrylic acid with 1-5C in the alkyl gp.; (iv) 0.2-5 wt.% glycidyl (meth)acrylate; and opt. (v) 0-35 wt.% acrylic and/or vinyl monomers other than (i)-(iv), in the presence of a regulator contg. mercapto gp. and at least one OH gp., the copolymer having an av. mol.wt. of 800-2500; (b) one or more polyisocyanates and/or their partial reaction prods. with polyols, and contg. at least 2 NCO gps./mol on average, the ratio (a) to (b) being such that 1-1.3 NCO gps. from (b) are present per OH gp. in (a); and (c) opt. additives such as accelerators, adhesion aids, pigments and fillers. The adhesive compsns. have a low viscosity and can thus be applied using little or no solvent. The adhesives cure at low temps. e.g. of 80 deg.C or less and can thus be used for bonding heat-sensitive materials such as plastics.