Protect aramid materials from UV-induced damage by ANF and ANF/light stabilizer composites

Aramid materials have been applied in many important civil and military fields. But a major drawback to aramid materials is the susceptibility to UV-induced damage. In this work, aramid nanofibers (ANFs) and ANF/nano-ZnO composites were used to protect aramid materials from UV-induced damage. ANF protective layer was created on the surface of aramid fibers, and the ANF-coated aramid fibers could be further prepared to aramid paper. Moreover, ANF/nano-ZnO composites were synthesized and used for stronger UV-blocking ability. ANFs provided effective protection to aramid material. The properties after UV exposure (about 9.3 years in the natural environment) were largely improved: ANFs improved the retention rate of strength by 17.96% for aramid fibers and by 16.93% for aramid paper. ANFs also showed synergistic effect with UV-absorbing inorganic nanoparticles. After UV exposure, the tensile strength of aramid paper with ANF/nano-ZnO composites was even higher than the initial value (121.55%), and the retention rate of strength was 2.43 times higher than the original aramid paper.