Resistance to vacuum ultraviolet irradiation of nano-TiO2 modified carbon/epoxy composites

Abstract

Nano-TiO2 modified composites, including TiO2 + EP648 and M40/TiO2 + EP648, were fabricated, in which the nano-TiO2 particles were dispersed in an EP648 epoxy matrix using a high-speed shearing emulsification technique. A jet type of vacuum ultraviolet (VUV) source was used to simulate the VUV spectrum in space and acquire various doses of VUV irradiation. In terms of the changes in specific-area mass loss and surface morphology, the resistance to VUV irradiation of the TiO2 + EP648 and M40/TiO2 + EP648 nanocomposites was evaluated. Experimental results showed that compared to the EP648 epoxy and M40/EP648 composite, the specific-area mass loss of the TiO2 + EP648 was decreased by 44% and that of M40/TiO2 + EP648 composite by 38%, respectively. By increasing the dose of VUV irradiation, the internal layer shear strength of the M40/TiO2 + EP648 increased gradually, while that of the M40/EP648 showed a decreasing trend. After irradiation, the surface of the M40/TiO2 + EP648 changed a little, but that of the M40/EP648 was damaged severely. It was indicated by means of scanning electron microscopy and atomic force microscopy observations that the VUV damage occurred mainly in the epoxy matrix, while the carbon fibers showed good resistance to irradiation.