Tribological and Electrical Properties of Silica-Filled Epoxy Nanocomposites

The tribological and electrical properties of epoxy composites filled with nano-sized silica particles are studied and discussed in this article. To enhance the interfacial interaction between the fillers and the matrix, nanoparticles were pretreated with silane coupling agent. Dry sliding wear tests were carried out with configuration of composite sample on a rotating steel disc. Electrical measurements such as AC breakdown voltage, at 50 Hz, high voltage-low current arc resistance and wet tracking resistance were carried out. The results reveal the influence of nanosized silica loading on wear resistance of the epoxy. It is observed that 10 wt% loading of silica is very effective in reducing the wear loss. With further increase of silica filler loading, the nanoparticles agglomerated and resulted in increase of the specific wear rate. The influence of silica particles on the specific wear rate is more pronounced under sliding wear situation. The influence of silica particle loading on epoxy is evident in the results of electrical parameters like dielectric strength, arc resistance and tracking resistance. These parameters showed improvement with filler loading up to 15 wt% and beyond this value of filler loading noticeable deterioration was observed. The effects of electrical stresses in the morphologies of the surfaces of epoxy nanocomposites are discussed. POLYM. COMPOS., 32:2038-2050, 2011. (C) 2011 Society of Plastics Engineers