Abstract:Polyimide (PI) has excellent high and low-temperature resistance, mechanical properties and corrosion resistance, but its poor intrinsic thermal conductivity limited its application in the electronic industry, aviation, aerospace and other fields. Introducing thermal conductive fillers into PI is an effective way to improve the thermal conductivity of PI composites. In this paper, the preparation methods of PI-based thermal conductive composites were summarized firstly; then the connected status of the thermal conductive fillers in PI matrix were mainly elucidated, that was, the dimension of space thermal conductive paths constructed by thermal conductive fillers in PI matrix, including one-dimensional, two-dimensional, quasi-three-dimensional and three-dimensional thermal conductive paths, and the performance of thermal conductivity of PI-based composites with different thermal conductive paths was accordingly described. Furthermore, the basic thermal conductivity model for PI-based composites was briefly introduced. Finally, the future research direction of PI-based thermal conductivity composites was put forward.