Patent ID: 8530053
Filing Date: 2013-09-10
Classification: C08G,C08K,C08L,Y10T

Abstract:
1. A heat-resistant composite material having, as a matrix, a cured epoxy resin, said composite material produced by: impregnating a reinforcing fiber with an anionic polymerizable epoxy composition; and anionically polymerizing the anionic polymerizable epoxy composition to form the cured epoxy resin; wherein the anionic polymerizable epoxy composition consists of an epoxy resin component and an anionic polymerization initiator; said epoxy resin component consisting of at least one epoxy compound having two epoxy groups per molecule, at least one epoxy compound having three or more epoxy groups per molecule or a combination thereof; said anionic polymerization initiator consisting of at least one alkali metal salt of a monofunctional carboxylic acid or a combination of at least one alkali metal salt of a monofunctional carboxylic acid and at least one alkali metal salt of a polyfunctional carboxylic acid without having a repeating unit, wherein the anionic polymerization initiator, as a whole, has a salted carboxyl functionality of less than or equal to 1.5 salted carboxyl groups per molecule; wherein said reinforcing fiber is at least one kind selected from the group consisting of carbon fiber and glass fiber; and wherein the cured epoxy resin exhibits a maximum loss tangent value at 1 Hz of 0.1 or less at 300° C. or below and a local maximum loss tangent value of 0.1 or less at 300° C. or below.