Structural Design and Research Progress of Thermally Conductive Polyimide Film – A Review

Currently, heat accumulation has seriously affected the stabilities and life of electronic devices. Polyimide (PI) film with high thermal conductivity coefficient (λ) has long been held up as an ideal solution for heat dissipation. Based on the thermal conduction mechanisms and classical thermal conduction models, this review presents design ideas of PI films with microscopically ordered liquid crystalline structures which are of great significance for breaking the limit of λ enhancement and describes the construction principles of thermal conduction network in high‐λ filler strengthened PI films. Furthermore, the effects of filler type, thermal conduction paths, and interfacial thermal resistances on thermally conductive behavior of PI film are systematically reviewed. Meanwhile, this paper summarizes the reported research and provides an outlook on the future development of thermally conductive PI films. Finally, it is expected that this review will give some guidance to future studies in thermally conductive PI film. This review summarizes the progress in thermally conductive polyimide (PI) films, focusing on thermal conduction mechanisms and models. Liquid crystalline PI film can break the bottleneck of intrinsic thermal conductivity coefficient (λ) enhancement. Influencing factors on λ of filler‐strengthened PI film are discussed. Strategies of filler combination are involved. Future research and challenges of high‐λ PI films are also discussed.