Novel composites of copper nanowire/PVDF with superior dielectric properties

Novel copper nanowires (CuNWs )/poly(vinylidene fluoride) (PVDF) nanocomposites with high dielectric permittivity ([epsilon]') and low dielectric loss ([epsilon]") were prepared by a precipitation technique followed by melt compression. Their dielectric properties over the broadband frequency range, i.e. 10 super(1)-10 super(6) Hz, were compared with multi-walled carbon nanotubes (MWCNT)/PVDF nanocomposites prepared by the same technique. It was observed that the CuNWs/PVDF nanocomposites had higher dielectric permittivity, lower dielectric loss and thus significantly lower dissipation factor (tan [delta]) than the MWCNT/PVDF nanocomposites at room temperature. This behavior was ascribed to a higher conductivity of the fresh core of the CuNWs relative to the MWCNT, which provided the composites with a higher amount of mobile charge carriers participating in the interfacial polarization. Moreover, the presence of oxide layers on the CuNWs surfaces diminished the conductive network formation leading to a low dielectric loss.