A self-healing polyvinyl alcohol-based composite with high thermal conductivity and excellent mechanical properties

Conventional thermally conductive polymeric composites are prone to mechanical failures when deployed in dynamic environments, which results in loss of functionality and reduced service life. Herein, self-healing thermally conductive composites are fabricated by dispersing polydopamine (PDA) modified boron nitride (BN) and borate ions into polyvinyl alcohol (PVA) matrix. Due to the decreased thermal interface resistance and formation of thermal conduction channels, the 13 vol% BN-PDA/PVA composite endows an enhancement of 562% in thermal conductivity (1.007 W/mK) comparing with pure PVA (0.152 W/mK). In addition, the hydrogen bonds between BN-PDA and PVA chains and the borate bonds in dynamic borax/PVA networks impart a high self-healing efficiency of more than 80% and excellent mechanical properties in BN-PDA/PVA composites. This study provides a straightforward method for the preparation of thermal interface materials with fast recovery and long service life for next generation electronic packaging applications.