Thermal conductivity and electrical insulation of epoxy composites with graphene-SiC nanowires and BaTiO3

Graphene-SiC nanowires (GSiC(nw)), the composite of multilayered graphene sheets and SiC nanowires, was prepared through a carbothermal reduction process. By means of incorporating SiC nanowires into multilayered graphene sheets (GS), the propagation of electron between graphene layers was effectively suppressed and the thermal conductivity was enhanced. However, the electrical conductivity of EP (Epoxy) composites was increased by one order of magnitude, which indicated that the separating effect of SiC nanowires on the electrical properties of GS was not ideal enough. Therefore, BaTiO3 was introduced in EP composites. Experimental results revealed that the thermal conductivity of EP-BaTiO3 composites was increased by 2.8 times (0.6434 W/m.K) with 0.092 vol% GSiC(nw) doping. Additionally, the electrical conductivity and the breakdown voltage of EP-BaTiO3 composite decreased by 250.7% and 169.5% compared with neat EP, respectively. According to the thermal conductivity model, the thermal property of EP-BaTiO3 composites with 0.6 vol% GSiC(nw) can reach 128 W/m.K.