Healable, highly thermal conductive, flexible polymer composite with excellent mechanical properties and multiple functionalities

Flexible and electrically insulating polymers are ideal heat dissipation packaging materials for flexible electronic devices, but their inherent low thermal conductivity has gradually become a bottleneck for their application in high-performance flexible electronics. Here, we report a high thermal conductive polymer composite, which was synthesized by an effective and feasible method of implanting hydroxylated boron nitride nanosheets (hy-BNNSs) into self-healable elastomer material (SM). The introduction of hy-BNNSs endowed the composite with an ultrahigh in-plane thermal conductivity of 12.6 ± 0.71 W m−1 K−1 and excellent mechanical properties including superior flexibility, remarkable recovery ability and humidity stability. Moreover, the composite demonstrated the deformation recovery ability and dimensional stability at 70 °C, which are indispensable in flexible electronic applications, and are fairly rare in healable composites. Benefiting from dynamic characteristics of non-covalent hydrogen bonds and disulfide bonds within polymeric materials, the composite can restore the mechanical properties, heat dissipation properties, and dielectric properties. All the results demonstrate it an ideal candidate for thermal management in flexible electronic devices.