▎ 摘　　要

An effective approach to prepare polyimide/siloxane-functionalized graphene oxide composite films is reported. The siloxane-functionalized graphene oxide was obtained by treating graphene oxide (GO) with 1,3-bis(3-aminopropyl)-1,1,3,3-tetra-methyldisiloxane (DSX) to obtain DSX-GO nanosheets, which provided a starting platform for in situ fabrication of the composites by grafting polyimide (PI) chains at the reactive sites of functional DSX-GO nanosheets. DSX-GO bonded with the PI matrix through amide linkage to form PI-DSX-GO films, in which DSX-GO exhibited excellent dispersibility and compatibility. It is demonstrated that the obvious reinforcing effect of GO to PI in mechanical properties and thermal stability for PI-DSX-GO is obtained. The tensile strength of a composite film containing 1.0wt% DSX-GO was 2.8 times greater than that of neat PI films, and Young's modulus was 6.3 times than that of neat PI films. Furthermore, the decomposition temperature of the composite for 5% weight loss was approximately 30 degrees C higher than that of neat PI films. (C) 2015 Society of Chemical Industry