Polymer Composite with Improved Thermal Conductivity by Constructing a Hierarchically Ordered Three-Dimensional Interconnected Network of BN

In this work, we report a fabrication of epoxy resin/ordered three-dimensional boron nitride (3D-BN) network composites through combination of ice-templating self-assembly and infiltration methods. The polymer composites possess much higher thermal conductivity up to 4.42 W m(-1) K-1 at relatively low loading 34 vol % than that of random distribution composites (1.81 W m(-1) K-1 for epoxy/random 3D-BN composites, 1.16 W m(-1) K-1 for epoxy/random BN composites) and exhibit a high glass transition temperature (178.9-229.2 degrees C) and dimensional stability (22.7 ppm/K). We attribute the increased thermal conductivity to the unique oriented 3D-BN thermally conducive network, in which the much higher thermal conductivity along the in-plane direction of BN microplatelets is most useful. This study paves the way for thermally conductive polymer composites used as thermal interface materials for next generation electronic packaging and 3D integration circuits.