Ballistic Performance of E-Glass Polyester Composites Modified with Silane Treated Alumina Nanofibers

The use of light weight composites against ballistic threat is very important for survivability and mobility in defensive architecture including but not limited to carriages for mass transit, safe rooms, armed forces and law enforcement centers. However, the existing structures need to compete with wide variety of threats and require wide ranging capabilities yet affordable. This study presents the silane functionalization of alumina nanofibers and its effect on the ballistic performance of the E-Glass polyester composites. The composite panels with E-Glass/Polyester are fabricated with functionalized and non-functionalized alumina nanofibers. Alumina nanofibers are dispersed into the polyester resin using three-roll mill technique. The EGlass woven fabrics are wetted with modified polyester by hand layup followed by compression molding press which cures the panels with heat and pressure. The samples were cut to desired size, shape and are impacted using a 9mm, full metal jacket projectile. The ballistic limit increased with addition of functionalized alumina nanofibers. However, functionalization and ballistic performance dependency cannot be completely established. The optimum loading level of alumina nanofibers was determined based on the toughness results and the effect of dispersion of alumina nanofibers in polyester examined through TEM imaging. The dispersion state of silane treated alumina nanofibers in polyester complimented the flexure toughness obtained for 0.25wt% and 0.5wt% loading rates