Surface modification of BN/Fe3O4 hybrid particle to enhance interfacial affinity for high thermal conductive material

Abstract

A composite with high thermal conductivity was fabricated using anisotropic boron nitride (BN) and particle alignment techniques. Iron oxide nanoparticles introduced onto the BN surface acted as magnets that gave rise to effective particle alignment. Because of the weak interfacial affinity between filler and matrix, particles chipped during the process and the post-alignment composite had poor morphology. In order to enhance attraction at the interface, the particle surface was modified using a silane coupling agent and poly(tetramethylene glycol). The long carbon chain in the outer polymer layer became entangled with that of the epoxy matrix, resulting in enhancement of interfacial affinity and thermal conductivity. The thermal conductivity of the synthesized composite increased from 0.832 to 1.448 on 20 vol% of filler loading after particle orientation, and increased to 1.577 W/mK after polyol coating. These particle alignment and surface modifications suggest promising applications in the development of thermal interface materials.