High-Thermal-Transport-Channel Construction within Flexible Composites via the Welding of Boron Nitride Nanosheets

Abstract

Efficient heat dissipation is a prerequisite for further improving the integration of devices. However, the polymer composites are not satisfying heat dissipation. For that reason, high-thermal-transport channels were manufactured by the direct freezing method and boron nitride nanosheets (BNNS) were further welded by carbonization. Composites with high thermal conductivity (7.46 W m–1 K–1) were obtained by immersion in poly(dimethylsiloxane) (PDMS). Thermal conductivity enhancement of composites reached about 3900% at 15.8 vol % loading of BNNS. Besides, the composites maintained the structural flexibility of PDMS and allowed repeated bending and twisting. In addition, the PDMS composites exhibited excellent antistatic properties because of a conductive network formed by residual carbon. Therefore, dust could be avoided and the surface kept clean. This provides a better choice for thermal management materials and meets the antistatic requirements of the devices.