Epoxy resin composition for FRP, prepreg, and tubular molding produced therefrom

An epoxy resin composition, consisting essentially of (A) a bisphenol A epoxy resin, (B) an epoxy resin having oxazolidone rigs and having no isocyanate groups, (C) a curing agent, and (D) a thermoplastic resin which is soluble in a mixture of said bisphenol A epoxy resin (A) and said epoxy resin (B), said epoxy resin (B) being an epoxy resin having a structure represented by the following formula (2):

• wherein R each independently represents a hydrogen atom or a methyl group, R1 to R4 each independently represent a halogen atom, a hydrogen atom, or an alkyl group having 1 to 4 carbon atoms, R5 to R8 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R9 represents the following formula (3) or (4):
• wherein R′1 to R′4 each independently represent a hydrogen atom or an alkyl group having 1 to 4 on atoms;
• wherein R′1 to R′8 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms and R′9 represents a single bond, —CH2—, —C(CH3)2—, —SO2—, —SO—, —S—, or —O—, and wherein said bisphenol A epoxy resin (A) is a mixture of a bisphenol A epoxy resin which has an epoxy equivalent of 300 or less and is liquid or semisolid at normal temperatures and a bisphenol A epoxy resin which has an epoxy equivalent of 400 or more and is solid at normal temperatures.