Thermal conductivity and electrical insulating properties of epoxy composites mixed with boron nitride and zinc oxide whisker

Phenolic epoxy resin (EP) is widely used in electronics because of its excellent electrical insulating pro-perties. The thermal conductivity of EP is low, and filling the highly conductive thermal inorganic fillers is an effec-tive way to construct the thermal conductive pathway of the thermal transport frame to improve the thermal conductivity of polymer composites. In this paper, the hexagonal boron nitride (h-BN)-four needle zinc oxide whisker (T-ZnOw)/EP composite was prepared by solution blended and hot-compaction process. The microstructures aspects, phase structures, thermal conductivity and electric insulating propertis of composites were systematically characterized and analyzed. The results show the h-BN-T-ZnOw/EP composite has good thermal conductivity and electrical insulating properties. When h-BN-T-ZnOw loading is 30wt%/5wt%, the thermal conductivity at 25℃ is 0.55 W/(m·K), which is 2.9 times higher than that of EP, and its volume resistivity is greater than 10¹⁵ Ω·m.