Study on impact resistance of Nano‐SiO₂ reinforced STG/Kevlar composites

Abstract

As a flexible protective material, shear thickening gel (STG)/Kevlar composite still has great potential to improve its impact resistance. In this paper, a novel STG/SiO 2 /Kevlar flexible protective composite was prepared by impregnating STG/SiO 2 into Kevlar. Due to the excellent SiO 2 enhancement effect, the STG/SiO 2 /Kevlar exhibited a higher safeguarding property than the STG/Kevlar.The maximum yarn pull-out force of STG/SiO 2 /Kevlar reached 61.7 N, which was higher than the 41.9 N of STG/Kevlar. The uniform puncture results showed that the maximum bearing capacity of STG/Kevlar and STG/SiO 2 /Kevlar increased by 116.8% and 215.3%, respectively, compared with pure Kevlar. The impact test results indicated that 20 layers of STG/SiO 2 /Kevlar could not be penetrated by the knife stab and 24 layers of STG/SiO 2 /Kevlar could not be penetrated by 7.62 mm pistol bullets. Finally, the enhancement mechanism of impact resistance of STG/SiO 2 /Kevlar composites was studied.

Novel shear thickening gel/high‐performance fiber reinforced flexible composites: Multi‐velocity impact and functional properties

“…[36] lay-up, lamination, and filling (Figure 5A-C). The impregnation method [53,54] is used to impregnate the reinforcement into the organic solvent, such as ethanol and acetone, in the ultrasonic cleaning machine to dilute STG so that STG can fully enter the fiber gap and combine tightly. The hand lay-up method [13,55] is to dilute STG with propanol and apply it uniformly on the surface of the fiber reinforcement (Figure 5D).…”

“…[13,42] In lamination method of STG/high-performance fiber flexible composites, the binding force between STG and the F I G U R E 5 Composites preparation methods: (A) impregnation; [53] (B) lamination; [35] (C) hand lay-up; [35] (D) hand lay-up, impregnation composite material SEM images; [13,53] (E) yarn pull-out force principle; the typical curve of pull-out force and the displacement; [13,53] (F) Impregnation. [54] (G) lamination; [11] (H) hand lay-up. [55] upper and lower reinforcement layers is poor, making the energy propagation unstable, which prevents the yarns from moving or cracking, causing the energy to propagate inconsistently.…”

Radiation effects on Kevlar fibers through high energy electron beam

“…[1][2][3][4] They have found utility in a variety of applications, such as anti-cutting materials, bulletproof vests, armor materials, and highstrength parachutes. [5][6][7][8] However, because the microstructure of aramid fibers is formed under non-equilibrium conditions, they are regarded as thermodynamically metastable materials that are sensitive to the surrounding environment. 9 With the expansion in their application domains, aramid fibers inevitably encounter environmental resistance problems.…”

“…Aramid fibers have high strength, high modulus, low weight, and good heat resistance 1–4 . They have found utility in a variety of applications, such as anti‐cutting materials, bulletproof vests, armor materials, and high‐strength parachutes 5–8 . However, because the microstructure of aramid fibers is formed under non‐equilibrium conditions, they are regarded as thermodynamically metastable materials that are sensitive to the surrounding environment 9 .…”

Synthesis and modification of poly (p‐phenylene terephthalamide) for production of light‐weight hybrid composite armors reinforced with polymer composite nanofiber mats

“…One of the recently most widely discussed technology that has demonstrated ability to improve ballistic resistance in soft body armor design studies is liquid body armor technology, which involves the impregnation of high-performance fiber-based fabrics with a shear thickening fluid (STF). [34][35][36][37][38] Research efforts are therefore underway to develop different designs to improve the energy absorption capacity of para-aramid fabrics through interply/intraply hybridization with different types of synthetic and natural fibers, layering of different materials or matrices and impregnation with STF, micro/nano-particles or the combination of these. [39][40][41] However, the contribution of polymer-based nanofiber mats to the ballistic impact response of the textile laminated armor system has not yet been reported in the open literature, despite the promising improvement in the mechanical properties of composites with a very small nanofiber reinforcement (<10 wt%) due to their extremely high surface area/mass ratio.…”