Tuning Electrical and Thermal Properties in Epoxy/Glass Composites by Graphene-Based Interphase

Multiscale epoxy/glass composites were fabricated by using E-glass fibers (GF) coated with different types of graphene nanosheets deposited by electrophoretic deposition. Graphene oxide (GO) was first synthesized using modified Hummer’s method and its subsequent ultrasonication in de-ionized water created a stable suspension of GO. GF were immersed in the water/GO suspension near a copper anode. The electrical potential applied between the electrodes caused GO to migrate towards the anode. Moreover, the GO coated yarns were exposed to hydrazine hydrate at 100 C to obtain reduced graphene oxide (rGO) coated yarns. Both GO and rGO coated GF yarns were used to create unidirectional epoxy-based multiscale composites by hand lay-up. The presence of a conductive rGO coating on GF improved both the electrical and thermal conductivities of composites. Moreover, enhanced permittivity was obtained by rGO based epoxy/glass composites, thus giving the option of using such structures for electromagnetic interference shielding.