Effect of filler concentration on breakdown in polymer nano-composites

Today nanotechnology has created a new dimension to enhance the properties of existing conventional insulating material. Polymer nano-composites belong to such type of material which shows improved insulation properties and dielectric behavior in high voltage engineering application due to their unique properties and compact size of insulation. Recently, the research focuses on determining the characteristics of various polymer-filler combination to obtain better insulation material with excellent electrical properties. In our work we focused mainly on the preparation of epoxy (Bisphenol-A) based nano-composites with different insulating fillers like TiO₂, Al₂O₃ and ZnO of very low concentration (0.1-1.5%), small thickness (100-500 microns) and homogeneous distribution of fillers. Breakdown tests were conducted on these nano-composite samples and their breakdown strengths are determined. The results showed that the breakdown voltage is found to vary for different nano-composites based on the properties of nanofillers. And it is influenced by the type of the fillers and the different nano-composites show improved electrical behavior at critical concentration of filler.