Relationship between dispersion state and reinforcement effect of graphene oxide in microcrystalline cellulose–graphene oxide composite films

Abstract

In this study, highly ordered, flexible, homogeneous and reinforced microcrystalline cellulose (MCC)–graphene oxide (GO) composite films regenerated from MCC/1-butyl-3-methylimidazolium chloride ([Bmim]Cl) solutions were prepared, and their nanostructures, thermal stability and mechanical properties were investigated by Fourier-transform infrared spectra, X-ray diffraction spectra, scanning electron microscopy images, thermal gravimetric analyses and tensile strength measurements. Moreover, the effect of the dispersion state of GO in MCC/[Bmim]Cl solutions with varying GO contents was studied by rheological tests. The mechanical properties of composite films could be remarkably improved over those of pure MCC film and there is a close relationship between the dispersion state and reinforcement effect of GO. Specifically, in comparison with pure MCC film, the composite film containing 0.5 wt% of GO exhibits a 64.7% enhancement in tensile strength and an 85.1% enhancement in strain-to-failure whereas the mechanical properties of the composite films are inferior to that of pure MCC film when the GO content is higher than 1 wt%.