Relaxation processes and conduction mechanism of epoxy resin filled with graphene oxide

In this work, mono-layer and multi-layer graphene oxide were used as fillers to be mixed with epoxy resin, where water solution, ultrasonication and magnetic stirring were used to achieve an optimal dispersion. The dispersion state of graphene oxide was observed by both scanning electron microscope (short as SEM) and transmission electron microscope (short as TEM). Different relaxation processes were studied over a wide range of temperature and frequency by an impendence analyzer. The observed nonlinear relationship between the electrical conductivity and the applied electric field strength potentially can be applied for field grading. This was verified by electric field simulations. Based on the experimental results, the nature of the interface interaction between epoxy resin and graphene oxide, the relaxation processes and the conduction mechanism of the studied epoxy-based nanocomposites were discussed.