Low frequency dielectric response of multilayer graphene/epoxy nanocomposites

In this paper the properties of epoxy-based nanocomposites with multilayer graphene (MLG) as a filler are investigated. In particular dielectric properties, such as conductivity and polarization characteristics, are studied as a function of MLG filler content, ranging between 0.05 wt.% to 0.5 wt.%, through charging / discharging current measurements at the field of 25 kV/mm and two temperatures (20°C and 60°C). Experimental results show that steady-state value of the charging current (conduction current) increases remarkably with a higher filler content. Moreover, Fourier analysis of discharging currents shows that dielectric susceptibility at very low frequency is significantly affected by the addition of MLG nanoplatelets. These results indicate that even a small percentage of MLG nanofiller is able to modify the electrical properties of the final nanocomposite.