Effects of graphene reduction degree on thermal oxidative stability of reduced graphene oxide/silicone rubber nanocomposites

In this work, graphene oxide (GO) was prepared with a modified Hummers method and then reduced to different reduction degree by thermal treatment. The GO and reduced GO (RGO) samples were introduced into silicone rubber (SR) matrix to prepare nanocomposites. X-ray photoelectron spectroscopy, Raman spectra, X-ray diffraction, and transmission electron microscopy measurement were performed to detect the structure and morphology changes of GO and RGO sheets. The results showed that the reduction removed most of the oxygen-containing functional groups on the surface of GO, especially C-O-C group, and thus reestablished a graphitic network of sp(2) hybrid; by increasing the reduction temperature, the reduction degree of GO was increased, and meanwhile, the extent of exfoliation was increased. More importantly, tensile testing and thermogravimetric analysis revealed that RGO improved the mechanical properties and thermal oxidative stability of SR nanocomposites. The improvement enhanced with increasing the reduction degree of GO simultaneously.