A self-healing silicone/BN composite with efficient healing property and improved thermal conductivities

Abstract

Polymer dielectric composites with excellent thermal conductivity have received increasing attention in the modern electronics industry due to their outstanding thermal management performance. However, conventional polymers used for the thermally conductive composites usually suffer from accidental mechanical failure, causing decrease in service life or loss of functionality. In this work, we prepared a self-healing silicone/BN composite simultaneous with high thermal conductivity, high self-healing efficiency and low electrical conductivity. Silicone cross-linked by DA adduct was used as polymer matrix and BN was used as thermally conductive filler. The self-healing silicone/BN composite exhibited a high self-healing efficiency of higher than 90% and an enhancement of 544% in thermal conductivity at BN content of 50 wt%. The self-healing composites presented excellent thermal management performance. The excellent self-healing properties were attributed to the thermal reversibility of the DA reaction and the flexibility of the siloxane molecules. In addition, the self-healing silicone/BN composite with 50 wt% of BN exhibited a low dielectric dissipation factor of 0.017 and an enhancement of 568% in tensile strength.