Effect of the degree of crystallinity on the electrical properties of MWCNT filled poly (ethylene-co-ethyl acrylate)/LDPE blend composites prepared by melt mixing

Poly(ethylene-co-ethyl acrylate) (EEA)/multiwalled carbon nanotubes (MWCNTs) master batches are prepared via melt mixing to investigate the effect that blending low density polyethylene (LDPE) into the master batch has on their electrical properties. Blending LDPE into the EEA/MWCNT master batches with a relatively low ratio of LDPE to EEA improves the electrical conductivity and lowers the percolation threshold as a result of the increase in the dielectric constant of EEA/LDPE blend resin and a better dispersion of MWCNTs. The electrical conductivity of the blend composite peaks at 20% LDPE and is inversely proportional to the degree of crystallinity of the composite. The average size and the number of the MWCNT aggregates decreases after LDPE blending, thus the better distribution is obtained for the MWCNTs without disturbing the formation of conducting paths caused by the presence of crystallites.