Study of SiO2 Nanoparticles on the Improved Performance of Epoxy and Fiber Composites

SiO2-epoxy and SiO2-glass-fiber epoxy nanocomposites were prepared to study the influence of SiO2 nanofiller particles on the mechanical properties. The size and concentration of free volume were tested by positron annihilation spectroscopy. The experimental results demonstrate that uniform dispersion of nanoparticles play an important role in promoting the comprehensive performance of nanocomposites. 115, 13, and 60% increase have been achieved at 3 wt% of nanoparticles for the tensile strength, tensile modulus, and impact strength, respectively. The studies on the effects of SiO2 nanoparticles on the properties of glass-fiber composites show that the SiO2 nanoparticles can generally promote their properties especially the bend strength that ends up with 69.4% enhancement. This is attributed to the promoted bonding forces between glass fibers and matrices owing to the presence of nanoparticles.