An efficient approach for constructing 3-D boron nitride networks with epoxy composites to form materials with enhanced thermal, dielectric, and mechanical properties

Thermally conductive epoxy composites of 3-D boron nitride (BN) networks were synthesized via a facile template method, wherein an epoxy was infiltrated into the network. The 3-D BN network skeletons, which use polystyrene (PS) microspheres as a framework support, were prepared by hot compression and ablation techniques. Field emission scanning electron microscope indicated that the content of BN filler and its dispersion greatly influences the integrity and density of the resultant network. With a BN loading of 40 vol%, the composites showed a maximum thermal conductivity of 1.98 W mK −1 , which is 1000% times higher than the pristine epoxy material. In addition, the thermal stabilities, mechanical properties, and dielectric properties of the fabricated BN/epoxy composites were also largely improved. This facile method is an effective approach to designing and fabricating composites with high thermal conductivities.