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 self-healing in thermal conducting composites is quite challenging.Herein,we choose a flexible poly(dimethylsiloxane) polymer material (PDMS-COOH) 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-1·K-1,which is 16 times that of PDMS-COOH (0.03 W·m-1·K-1).At room temperature,self-healing efficiency of PDMS-COOH-CG10 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 self-healing at room temperature,the thermal conduction temperature near the damage was basically restored to the level of the pristine sample.