Morphology and electrical properties of graphene-epoxy nanocomposites obtained by different solvent assisted processing methods

We report a comparative study of graphene nanoplatelets (GNPs)-epoxy nanocomposites with enhanced electrical conductive properties obtained with two different processing techniques. In the first one (TEC1), the epoxy monomer was added to a previously produced GNP-chloroform suspension and after the evaporation of the solvent, the hardener was added. In the second technique (TEC2), the hardener was added to a GNP-tetrahydrofuran suspension and after the evaporation of the solvent, the epoxy monomer was added. Although there was good dispersion of GNPs in the epoxy matrix with both techniques, the nanocomposite based on TEC1 showed a slightly better dispersion than the one based on TEC2. Electric and dielectric characterization showed that it is possible to reach the electrical percolation threshold at reasonably low GNP contents.