Boron nitride based poly (phenylene sulfide) compsoites with enhanced thermal conductivity and breakdown strength

Dielectric polymer composites with high thermal conductivity and high breakdown strength have wide applications in electronic devices and electrical equipment. In this study, poly (phenylene sulfide) [PPS] and boron nitride (BN) were selected for preparing high thermal conductivity composites for high temperature insulation application. The composites were prepared by melt compounding to contain 0-40.0 wt% (BN). Laser flash method was used to measure the thermal conductivity. As a result, the composites exhibit significantly enhanced thermal conductivity when compared with the pure polymer. For instance, the composite sample shows an increase of thermal conductivity from 0.28 W/(m·K) (the pure PPS) to 1.21 W/(m·K) when it contains 40.0 wt% BN. Weibull statistical distribution was used to analyze the breakdown data and the characteristic breakdown strength was used to compare the breakdown strength of various samples. It was found that, except the sample containing the low concentration of BN filler, the composites show enhanced breakdown strength when compared with the pure PPS. Scanning electron microcopy (SEM) results show that the BN flakes are homogeneously distributed in the PPS matrix. Thermogravimetric analysis shows that the composites have increased thermal stability when compared with the pure PPS.