Effects of ZnO nanowire and silica coatings on the inter-yarn friction and ballistic properties of Kevlar fabrics

Abstract

This paper focused on improving the ballistic performance of plain weave (PW) and twill weave (TW) Kevlar fabrics without affecting the weight. Single layers of fabrics were subjected to two different surface coatings, one with ZnO nanowires (ZnO NW) and other with Silica nanoparticles. Tensile, inter-yarn friction and ballistic properties of bare and surface coated fabrics were evaluated and compared with each other. All types of PW fabrics were found to have superior tensile strain energy, inter-yarn friction and ballistic energy absorption than corresponding TW fabrics. Both ZnO NW and Silica coatings were found to significantly improve the strain energy, inter-yarn friction and ballistic energy absorption of fabrics with only less than 8% increase in the areal density of the fabrics. Among the two surface treatments, Silica coating was found to provide maximum improvement in properties. It increased the strain energy, yarn pull-out energy and ballistic energy absorption in PW fabrics by 67%, 694% and at least 240%, respectively. Also, it increased the strain energy, yarn pull-out energy and ballistic energy absorption in TW fabrics by 42%, 1350% and 387%, respectively. The work demonstrated promising ways of improving the ballistic performance of Kevlar fabrics.