Vertically Aligned Al₂O₃ Fiber Framework Leading to Anisotropically Enhanced Thermal Conductivity of Epoxy Composites

Abstract

With the development of the modern electronic devices, efficient heat removal via thermal management materials in a low filling load has become one of the most critical challenges. Herein, a biomass template method is used to produce 3D alumina skeleton with one‐directionally arranged alumina fibers as the thermal conductive filler of epoxy composites. Thermal conductive composites with anisotropically enhanced thermal conductivity are prepared by impregnating epoxy resin into the 3D alumina skeleton. At an alumina load of 17.7 wt%, the composite exhibits a high out‐of‐plane thermal conductivity of 0.72 W m −1 K −1 (3.27 times of pure epoxy) and an in‐plane thermal conductivity of 0.38 W m −1 K −1 , respectively. When compared with literatures in terms of the thermal conductivity enhancement per unit mass of filler, the samples are on the top. By using the biomass template method to construct 3D anisotropic structure, it is effective to improve the out‐of‐plane thermal conductivity of the composites, which exhibits strong potential for thermal management applications.