Novel electrical conduction properties obtained in few-layer graphene/epoxy nanocomposites

In this paper, we propose to study the impact of very low filler content (0.005 wt.%) of graphite nanoflakes (80 nm), multi-layer (5-20 nm) and few-layer (1-2 nm) graphene on the electrical conductivity of an epoxy nanocomposite. The results highlight that an improvement of the quality of the exfoliation process of graphene, particularly in few-layer graphene/epoxy, allows decreasing the DC electrical conductivity (by a factor 100 compared to neat epoxy) in a large range of electric field from 1 to 10 kV/mm. This novel property could allow decreasing space charge trapping within the insulator bulk at the origin of long-term electrical ageing.