Modified epoxy-(meth)acrylate(s) for prods. with low water absorption - obtd. by esterification of epoxide oligomers, e.g. bisphenol=A di:glycidyl ether, with (meth)acrylic acid and satd. mono:carboxylic acid

摘要

Modified epoxy-(meth)acrylates (I) based on Bisphenol A are claimed, in which the addn. prods. contain mixed esters of epoxide oligomers (II) with (meth)acrylic acid (III) and a satd. mono-carboxylic acid (IV), with the OH gps. formed in the addn. reaction being completely or partly esterified with (IV). Prodn. of (I) comprises 1-stage reaction of (II) with (III) and the anhydride of (IV), with mol. ratio (epoxy gps):(COOH gps. in III) = 1:(0.4-1.5), pref. 1:(0.6-0.8) and mol. ratio (epoxy gps):(COOH gps. in III) = 1:(0.4-1.5), pref. 1:(0.6-0.8) and mol. ratio (epoxy gps.):(anhydride) = 1:(5-0.05), pref. 1:(0.4-0.2). Specifically (I) are modified with the anhydrides of (un)substd. (cyclo)aliphatic or aromatic mono-acids, pref. Ac20 or (PhCO)20; the addn. prod. contains 20-50 (pref. 30-40) mol. % (meth)acrylate gps. and 5-80 (pref. 40-20) mol. % ester gps. derived from (IV), w.r.t. the max. possible no. of ester gps.; mol. ratio (III):(anhydride of IV) = (40:60)-(95:5) pref. (60:40)-(80:20), with the total no. of mols. of both equal to the no. of mols of epoxy gps. reaction is carried out at elevated temps. with addn. of the anhydride after 50-70% reaction of (III); a polymerisation inhibitor is added in 2 portions, consisting of 50-80 (pref. 70)% at the start of reaction and the other 20-50 (pref. 30%) with the anhydride after 50-70% reaction. USE/ADVANTAGE - (I) are useful for the prodn. of mouldings, printing plates, adhesives, sealants, dental filling materials, coating materials etc. Modified epoxy-(meth)acrylates in which the OH gps. in the addn. prod. (e.g. BIS-GMA) are blocked by esterification with (IV) are obtd. This gives stable polymerisable prods. with low polymerisation shrinkage, low hydrophilicity and low residual double bond content after polymerisa