An effective in situ reduction strategy assisted by supercritical fluids for the preparation of graphene - polymer composites

Abstract

The chemical/thermal in situ reduction of graphene oxide (GO) in GO-polymer composite is consistently challenged by the presence of undesirable chemical residues/temperature degradation restriction of the polymer. In order to tackle this problem, an effective in situ supercritical fluid reduction strategy comprising of supercritical CO2 and ethanol binary system under N2 atmosphere was developed by stepwise comparison of different reduction methods for graphene oxide-polyvinyl alcohol (GO-PVA) composite films. The resulting rGO-PVA composite films comprising of 10 wt% rGO showed an electrical conductivity of 51.7 S/m-and Young's modulus of 3.1 GPa. Different weight loadings of GO in the polymer composite films were found to affect the electrical and mechanical properties of the resulting rGO-polymer films. The in situ supercritical fluid reduction strategy was demonstrated further for successfully obtaining rGO-polyethylene glycol films (rGO-PEG) and rGO-PVA fiber.