A Fast and Room-temperature Self-healing Thermal Conductive Polymer Composite

Thermal conducting materials may be damaged during long-term use, resulting in the increase of thermal resistance and therefore inefficient heat dissipation. The introduction of self-healing ability may solve this problem, but the realization of fast and room-temperature selfhealing in thermal conducting composites is quite challenging. Herein, we choose a flexible poly(dimethylsiloxane) polymer material(PDMSCOOH) as the matrix and graphene nanosheets as the thermal conductive filler to prepare a new kind of thermal conductive polymer composite(PDMS-COOH-CG) that can quickly self-heal at room temperature. The thermal conductivity of PDMS-COOH-CG10 with 10% of graphene content is 0.48 W·m·K, which is 16 times that of PDMS-COOH(0.03 W·m·K). At room temperature, self-healing efficiency of PDMS-COOHCG10 based on tensile strength can be 53.8% for 30 s and 84.6% for 24 h. Dynamic infrared thermal imaging dipicted that after 2 min of selfhealing at room temperature, the thermal conduction temperature near the damage was basically restored to the level of the pristine sample.