BN/PSZ composite polymer: A molecular dynamics study and experimental characterization

Abstract

The excellent insulation, stability, and processability of Polysilazane (PSZ) and its composites have attracted attention. However, due to complex crosslinking and pyrolysis processes and its amorphous nature, numerical simulations on the crosslinking and properties of PSZ and its composites are scarce. This study focuses on a BN/PSZ polymer composite by blending Boron Nitride (BN) with PSZ. Molecular dynamics (MD) investigate crosslinking and thermal conductivity. Results show PSZ forms a network structure during crosslinking, enhancing thermal conductivity pathways with BN, resulting in a significant increase in composite thermal conductivity. With 100 % crosslinking and 79.03 wt% BN, thermal conductivity reaches 4.130 W/(m·K). At the same time, BN/PSZ mixture was prepared by the blending method. After heating and curing the mixture at 250 °C with Nitrogen atmosphere, the obtained cured product was pressed into tablets using a tablet press to observe its thermal conductivity. Comparing the simulation results with the actual test results, the maximum error rate was only 6.05 % at a BN of 60 vol%, which provides highly valuable references for the research on nanofiller/PSZ composites.