Highly Thermal Conductive Graphite Films Derived from the Graphitization of Chemically Imidized Polyimide Films

With the large-scale application and high-speed operation of electronic equipment, the thermal diffusion problem presents an increasing requirement for effective heat dissipation materials. Herein, high thermal conductive graphite films were fabricated via the graphitization of polyimide (PI) films with different amounts of chemical catalytic reagent. The results showed that chemically imidized PI (CIPI) films exhibit a higher tensile strength, thermal stability, and imidization degree than that of purely thermally imidized PI (TIPI) films. The graphite films derived from CIPI films present a more complete crystal orientation and ordered arrangement. With only 0.72% chemical catalytic reagent, the graphitized CIPI film achieved a high thermal conductivity of 1767 W center dot m(-1)center dot K-1, which is much higher than that of graphited TIPI film (1331 W center dot m(-1)center dot K-1), with an increase of 32.8%. The high thermal conductivity is attributed to the large in-plane crystallite size and high crystal integrity. It is believed that the chemical imidization method prioritizes the preparation of high-quality PI films and helps graphite films achieve an excellent performance.

Automated summary

With the increasing application of electronic equipment, the need for effective heat dissipation materials is growing. In this study, high thermal conductive graphite films were produced by chemically modifying polyimide films. The results showed that the chemically modified polyimide films had higher strength, thermal stability, and crystal arrangement. The graphite films derived from these modified films exhibited larger crystal size and higher thermal conductivity.