Enhancing the Thermal Conductivity of Graphene-based Thermal Interface Materials by Polyimide Fiber Intercalation

Temperature is an important factor affecting the reliability of electronic components. High temperature environments have a direct negative impact on the performance and lifetime of electronic devices. Graphene, a remarkable two-dimensional carbon material renowned for its exceptional in-plane thermal conductivity properties, faces a significant challenge due to the high phonon transport barrier at the van der Waals interface between its layers. This poses a limitation for meeting the heat dissipation requirements of cutting-edge electronic devices. In this study, a graphene composite film with polyimide (PI) fiber intercalation is presented. Graphene oxide (GO) and PI composite films were obtained by solution blending of PI fibers and GO. Subsequently, the GO/PI film was graphitised and calendered at high temperature to obtain the dense g-GO/PI film. The PI fiber intercalation constructs a three-dimensional thermal conductivity network that enables the g-GO/PI film to have high in-plane thermal conductivity (1406 W m-1K-1) and through-plane thermal conductivity (21.3 W m-1 K-1). The exceptional thermal conductivity of the graphitized GO/PI film (g-GO/PI) as a thermal interface material confirms its superior thermal management capability compared to copper foil. This presents an enticing prospect for the integration of advanced thermal management systems in future high-performance flexible electronic devices.