Application of h‐BN particles using Ca‐assisted carbothermal reduction nitridation to high‐thermal‐conductive resin/h‐BN composites

Abstract

AbstractHexagonal boron nitride (h‐BN) particles exhibit high thermal conductivity and are promising fillers for resin filling. However, h‐BN particles are plate‐like particles with thermal anisotropy in the planar and thickness directions. Therefore, their applications are limited due to low thermal conductivity in the direction of the thickness of a resin sheet filled with h‐BN particles. In this study, we control the size and thickness of h‐BN particles using carbothermal reduction nitridation (CRN), which involves the carbothermic reduction of boric oxide in an N2 gas atmosphere and develop them into resin sheets. In CRN using a CaO promoter, a novel method is developed to control the shape, size, and thickness of h‐BN particles. Using h‐BN particles grown in the thickness direction, we have successfully provided resin sheets with high thermal conductivity.