Effects of silica morphology on the shear‐thickening behavior of shear thickening fluids and stabbing resistance of fabric composites

Abstract

Shear‐thickening fluid (STF) refers to a system where nonaggregating solid particles are suspended in a specific fluid. Due to its unique viscosity variation, STFs have attracted a lot of attention as soft body armor materials for impact protection. In this work, two kinds of STFs were designed using polyethylene glycol (PEG) and spherical or irregularly shaped silica particles. Rheological results showed that shear thickening can even occur at lower shear rates in the irregularly shaped silica‐based STF; however, the thickening range of the spherical silica‐based STF was broader. Meanwhile, the composites prepared with STFs and aramid fabrics exhibited better antistab properties than neat fabrics. Compared to composite prepared with irregularly shaped silica‐based STF, spherical silica‐based STF/aramid composite had better stabbing resistance. In addition to the binding effect of silica particles to the fiber bundle, it was considered that when the fabric composite was subjected to impact, spherical particles were easier to slide so that the STF was more likely to be thickened to achieve a greater viscosity, resulting in the better stabbing resistance performance. Our studies will provide guidance for the design of the high‐performance soft body armor equipment. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48809.

Fabric Impregnation with Shear Thickening Fluid for Ballistic Armor Polymer Composites: An Updated Overview

“…They are composed of fixed yarns called warp, while the weft yarns are inserted under and over them [ 28 , 43 , 79 , 80 ]. Typically, as mentioned before, aramid, UHMWPE, polyphenylenebenzobisoxazole, and nylon are used in soft armor to provide protection from bullets [ 36 , 81 , 82 , 83 , 84 ] and stabbing [ 52 , 54 , 55 , 85 , 86 , 87 ], as they present high-strength/modulus fibers and offers the proper strength to impact and trauma according to current security norms. Table 4 presents the parameters related to fabric that influence the ballistic performance.…”

New Research Trends for Textiles

“…Work has been conducted to look at the effect of the silica nanoparticle morphology (spherical or irregular) on the efficiency of the shear thickening fluid of aramid fabrics against stabbing [202]. The best results were obtained with spherical nanoparticles.…”

Impact behavior of aminosilane functionalized nanosilica based shear thickening fluid impregnated Kevlar fabrics

“…Several works have been done to support the above statement. [21][22][23][24][25][26] The padding of STF into the single/ multilayer Kevlar composites improves energy absorption at high velocities. 27 The functionalization of nanosilica with silane coupling agents further improves the energy absorption of fabrics due to the formation of siloxane bonds.…”