Effects of different amine-functionalized graphene oxide on the mechanical and thermal properties of polyimide composites

The utilization of functionalized graphene oxide as nanofillers has attracted significant attention in the development of high-performance composite materials. In this study, amine-functionalized graphene oxide (AFGO) by different amines, including p-phenylenediamine- (PPD-GO) and 4, 4’-diaminodiphenyl ether (ODA-GO), respectively, was prepared and used to synthesize a series of polyimide (PI) composite membranes via in situ polymerization method. The PPD-GO/PI and ODA-GO/PI composite membranes exhibited much higher mechanical and thermal properties than that of neat PI, owing to the diverse interfacial interaction and the surface architecture behavior. Compared to neat PI, the tensile strengths were enhanced 14.6% and 14.5%, the tensile modulus were enhanced 26.9% and 23.2%, and the Tg increased by 9°C and 17.5°C of the PI composite membrane containing 0.3 wt% PPD-GO or ODA-GO, respectively. This study provides a guidance for the development of high-performance PI composite materials through the regulated interfacial structure via the moderate chain length.