title: Flexible polyimide films hybrid with functionalized boron nitride and graphene oxide simultaneously to improve thermal conduction and dimensional stability.
abstract: Coupling agent-functionalized boron nitride (f-BN) and glycidyl methacrylate-grafted graphene (g-TrG) are simultaneously blended with polyimide (PI) to fabricate a flexible, electrically insulating and thermally conductive PI composite film. The silk-like g-TrG successfully fills in the gap between PI and f-BN to complete the thermal conduction network. In addition, the strong interaction between surface functional groups on f-BN and g-TrG contributes to the effective phonon transfer in the PI matrix. The thermal conductivity (TC) of the PI/f-BN composite films containing additional 1 wt % of g-TrG is at least doubled to the value of PI/f-BN and as high as 16 times to that of the pure PI. The hybrid film PI/f-BN-50/g-TrG-1 exhibits excellent flexibility, sufficient insulating property, the highest TC of 2.11 W/mK, and ultralow coefficient of thermal expansion of 11 ppm/K, which are perfect conditions for future flexible substrate materials requiring efficient heat dissipation.
authors.affiliation: Department of Chemical and Materials Engineering, National Chin-Yi University of Technology , No. 57, Sec. 2, Chungshan Road, Taipin District, Taichung 41170, Taiwan.
authors.forename: Mei-Hui
authors.initials: MH
authors.lastname: Tsai
authors.forename: I-Hsiang
authors.initials: IH
authors.lastname: Tseng
authors.forename: Jen-Chi
authors.initials: JC
authors.lastname: Chiang
authors.forename: Jheng-Jia
authors.initials: JJ
authors.lastname: Li