Epoxy/alumina nanoparticle composites. II. Influence of silane coupling agent treatment on mechanical performance and wear resistance

Two silane coupling agents (SCAs) were used to treat alumina nanoparticles to improve nanoparticle dispersion into the polymer matrix. [3-(2-Aminoethylamino)-propyll-trimethoxysilane [a reactive silane coupling agent (RSCA)] was able to form covalent bonds with both the reinforcing agent (alumina nanoparticles) and the epoxy matrix, whereas 3-(trimethoxysilyl) propyl methacrylate (a nonreactive SCA) could not covalently interact with the epoxy resin. The strengthening of the filler-matrix interactions by means of covalent bonds resulted in improved flexural strength, strain, and especially, wear resistance. The wear rate and the weight loss of the RSCA-treated alumina nanoparticle composite were the best among the investigated composite samples and equal to these of the neat epoxy matrix. This improvement was due to better nanoparticle dispersion, a result of the SCA treatment of the alumina nanoparticles. (c) 2006 Wiley Periodicals, Inc.