Dielectric properties of epoxy and polyethylene nanocomposites

In recent years polymer nanocomposites have attracted wide interest with regard to enhancing polymer properties and extending their utility. It has been found that the dielectric properties have a close relationship with the interfacial behavior between the fillers and the polymer matrix in such composites. In this paper, a typical bisphenol-A epoxy with anhydride hardener system and linear low-density polyethylene were chosen as matrix polymers and a nanometric size aluminium oxide was used as filler. Both ultrasonic processing and Brabender mixing were used to obtain a fine dispersion of the fillers in polymers. The dielectric properties of the composites have been measured in the frequency domain from 10^-4 Hz to 10^-6 Hz. Morphological characterization was carried out by scanning electron microscopy. The difference in dielectric properties between the two polymers is discussed.