Response of silica-nylon6 nanocomposites to static and dynamic loading

Abstract

Silica-nylon6 composites were fabricated using two types of silica nanoparticle fillers with different surface modifications. Type A particles (treated with hexamethyldisilazane) were uniformly dispersed but only displayed weak long-range interaction with the nylon6 matrix; in contrast, type B particles (modified with 3-aminopropyltriethoxysilane) formed covalent bonds with the nylon6 chains but their dispersion is not good. The silica-nylon6 composites synthesized were subjected to quasi-static and dynamic tension to study the effects of strain rate and nano-particle fraction. Results show that compared to quasi-static loading, both pure nylon6 and the composites exhibit a higher strength but lower ductility under dynamic loading. With respect to the influence of the nano-particles, both particle types cause an increase in the elastic modulus and tensile strength. The effect of the two particles on ductility differs - particle A reduces ductility, while particle B decreases ductility under quasi-static loading but enhances it noticeably for dynamic loading. Particle B enhances the mechanical properties more significantly, especially in terms of ductility. These results suggest that ensuring strong particle-matrix bonding is more crucial than good particle dispersion. © 2012 Trans Tech Publications, Switzerland.