Dynamic mechanical and thermal behavior evaluation of an epoxy/anhydride/nano-aluminum oxide composite system

Abstract

The conventional properties of composites may be improved by incorporating the nanoparticles in polymer matrix to achieve high-performance polymer nanocomposites. In this respect, a commercial formulation of an epoxy electrical insulator was prepared by the chemical reaction of bisphenol A-based epoxy resin with an anhydride hardener and mixed with microsilica as filler. The effect of different contents of nano-aluminum oxide on dynamic mechanical and thermal properties of the cast epoxy composite was evaluated. The obtained result revealed that the effect of uniform dispersion of nanoparticles on storage modulus was as important as the filler content. In other words, increasing nanoparticle contents up to 10 wt% could not necessarily improve the properties of the nanocomposite while a uniform dispersion of nanofiller of just 1 wt% in a sample provided an efficient nanocomposite in which the values of storage modulus, dissipation factor and thermal stability were optimized. Furthermore, the combination of stiffness and high damping may be achieved in well-dispersed nanocomposites where strong interfacial interaction dominates between particle surface and polymer chain segments. This kind of sample possesses the highest thermal stability as well.