PREPARATION OF EPOXYLATED PHENOLIC RESINS BY REACTING POLYMERS FRO ARALKYL ETHERS AND PHENOLS WITH EPIHALOHYDRIN

摘要

1,169,045. Glass-cloth laminates. MIDLAND SILICONES Ltd. 19 July, 1968 [21 July, 1967], No. 33701/67. Heading B5N. [Also in Division C3] Laminates are prepared from glass cloth impregnated with a composition comprising an epoxylated phenolic resin prepared by: (A) forming a polymer by reacting together (I) an aralkyl ether of formula RSP1/SP(CH 2 OR) a , where R is a C 1-5 alkyl radical, RSP1/SP is a di- or tri-valent aromatic hydrocarbon or hydrocarbonoxy radical the nucleus of which may contain unreactive substituents, a is 2 or 3, and a molar excess of (II) a phenolic compound or a mixture of a phenolic compound and a compound containing one or more aromatic nuclei; (B) reacting the polymer formed in step (A) with an epihalohydrin, e.g. epichlorohydrin, in the presence of a hydrogen halide acceptor, e.g. NaOH. (I) may be p-xylyleneglycol dimethylether. (II) may be phenol, p-phenyl phenol or diphenylpropane optionally mixed with an aromatic hydrocarbon or an aromatic hydrocarbon ether. The products may be cured with conventional epoxy resin hardeners, e.g. polyamines and polycarboxylin acid anhydrides. In examples a resin prepared from p-xylyleneglycol dimethyl ether and phenol, which is subsequently reacted with epichlorohydrin and mixed with a polycarboxylic acid anhydride and 2,4,6 - tris (dimethylaminomethyl) phenol, is dissolved in methyl ethyl ketone and coated on to glass cloth. After procuring for 10 minutes at 130‹ C. and cooling, laminates were obtained by (a) pressing at 175‹ C. and 1000 p.s.i. for 10 minutes; (b) post curing at 250‹ C. for 20 hours.