Structural and AC Electrical Properties of (LDPE-MWCNTs) Polymer Nanocomposite.
Keywords:dielectric constant --- dielectric loss --- AC conductivity --- nanocomposites --- MWCNTs
In this paper, the effect of Multi Walled Carbon Nanotubes (MWCNTs) on AC electrical properties of (LDPE-MWCNTs) nanocomposites bulk has been studied. The (LDPE-MWCNTs) nanocomposites were prepared in different (MWCNTs) volume fraction which were (1%, 2%, 3%, 4%). Ultrasonic dispersion and magnetic stirring techniques were used to prepare the nanocomposites specimens using flash molds at standard conditions. The morphology of samples have been studied using (SEM) technique, which showed grain distribution at surface morphology and grain aggregates with increasing of MWCNTs vol.%. The FTIR spectrum of samples were measured and shown the type of bond for polymer and the addition of MWCNTs did not effect on the chemical structure of LDPE. The experimental results (XRD) showed the samples transmutation from semicrystalline to crystalline because increased ratio particle of MWCNTs. AC electrical properties were measured at room temperature with different frequencies; it is found that the dielectric constant increases with increasing the MWCNTs vol.%, but decreases with increasing frequency attributed to polarization effects of the nanocomposite. Also the dielectric loss of polymers composites has been measured. The results refer that the dielectric loss is reduced with increasing of frequency and the AC conductivity increases with the increasing of volume fraction of MWCNTs because of the increase of the charge carriers and formation of a continuous network of MWCNTs inside the nanocomposites.