Enhanced electrical properties in percolative low-density polyethylene/carbon nanotubes nanocomposites

Enhanced dielectric permittivity and conductivity are observed in low-density polyethylene/multiwall carbon nanotubes (LDPE/MWCNT) nanocomposites prepared via a melt-blending process and subsequent a hot-molding procedure when the volume fraction of MWCNT is near the percolation threshold. In comparison to some reported results, the present percolation threshold is high. The high percolation threshold may be attributed to the MWCNT, which are fractured easily during the melt-blending process due to the strong shear rate. For the percolative LDPE/MWCNT nanocomposite, the dielectric permittivity and conductivity at 100 Hz are about 200 and 10^-4 (S m^-1), respectively. The results are also explained by employing the well-known percolation theory. This LDPE/MWCNT nanocomposite, with high dielectric permittivity and high conductivity, may be considered as a potential shield layer material for use with HVDC insulators.