The R&D team of Protech published a paper online titled "Ballistic performance of UHMWPE fiber/waterborne polyurethane composite laminate against mild-steel core projectile and its damage mechanism" online in the Chinese core journal Acta Materiae Compositae Sinica on July 22nd, 2020. This paper provides significant guidance for the structural design of UHMWPE fiber/WPU composite laminates in engineering applications aimed at protecting against threats such as AK-47 or Type 56 semi-automatic rifles (GA141-2011 Level V).

Three kinds of thermoplastic resin, waterborne rubber, waterborne polyester and waterborne polyurethane, were used as resin matrix, and ultra-high molecular weight polyethylene (UHMWPE) fiber was worked as reinforcement. The unidirectional cross-ply structure bulletproof advanced composite laminates were prepared by hot-pressing process. The influences of thermoplastic resin matrix on mechanical behavior and ballistic response of bulletproof advanced composites were studied through ballistic impact test and mechanical test. The results show that: compared with the single thermoplastic resin system, UHMWPE fiber composite, which was fabricated with the thermoplastic resin mixed system, has better anti-penetration performance, higher tensile strength at break and higher interlaminar shear strength at break. This phenomenon is due to the higher utilization efficiency of UHMWPE fiber in the mixed resin system. Moreover, according to indirect tension mechanism induced by transverse compression together with membrane force effect caused by the larger deformation under ballistic impact, the anti-penetration performance of UHMWPE fiber composite is positively correlated with mechanical properties under quasi-static state, including tensile strength at break and interlaminar shear strength.