Latent Curing Agent Modified Epoxy Sizing Agent for High Modulus Carbon Fiber

ABSTRACT

A new kind of latent curing agent (LCA) for epoxy resin was synthesized to improve the properties of epoxy sizing agent for high modulus carbon fiber by the reaction of ethylenediamine with butylacrylate in equal molar ratios, and the chemical structure and thermal property of the LCA were studied with FTIR and TGA, respectively. Moreover, LCA modified epoxy resin used as sizing agent for high modulus carbon fiber was studied. The results show that the wettability of sized high modulus carbon fiber tends to increase due to the increase of LCA content in sizing agent on the surface of the carbon fiber; while absorbability of sized high modulus carbon fiber tends to decrease; and drape of the sized high modulus carbon fiber which indicates the shaping effect of the fiber changes with the content of LCA, and interlaminar shear strength (ILSS) of the sized high modulus carbon fiber/epoxy composites is improved to 78MPa, which increased by 8.6% compared with the composites reinforced by high modulus carbon fiber with unmodified sizing agent, indicating that using LCA modified epoxy resin as sizing agent for high modulus carbon fiber is a feasible method to improve the interfacial performance of high modulus carbon fiber/epoxy composites.