Thermosetting resin composition and prepolymer obtained therefrom

摘要: A thermosetting resin composition comprising (a) a polyfunctional maleimide, (b) at least one member selected from the group consisting of alkenylphenols and alkenylphenol ethers, (c) an allyl ester polyvalent carboxylic acid, or cyanuric isocyanuric acid prepolymer obtained by preliminarily heating can be used as solventless type varnish for impregnating, e.g. electric windings, preparing prepreg, give cured product with 120°-250° C. having excellent heat resistance class C (180° higher) electrical insulating properties.