Enhanced Thermal Conductivity of Dielectric Polydimethylsiloxane Composites by Size-Controllable Boron Nitride Nanosheets

Abstract

The evolution toward apace increasing power density of up-to-date electric equipment and semiconductor technology raises more requirements of high efficiency thermal management materials. In this study, we report polydimethylsiloxane (PDMS) composites containing size-controllable boron nitride nanosheets (BNNSs) as fillers, showing enhanced thermal conductivity yet superb electrical insulating property. At the same filler loading, BNNSs with the smaller size can increase the thermal conductivity of composites more effectively, and this trend becomes more noticeable at the higher filler concentration. Compared with the pristine PDMS, when the load of small size BNNSs reaches 23.1 wt%, the nanocomposite shows a thermal conductivity enhancement of about 300%. Furthermore, it exhibits exceptional electrical insulation.