The influence of weathering on the ballistic performance of an armor made with aramid fabric was for the first time investigated, by standard exposure related to degradation conditions of: (i) ultraviolet radiation (UV); (ii) moisten by washing (MW) and (iii) UV+MW. Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction (XRD) and scanning electron microscopy (SEM) characterized the modifications that occurred on the aramid fabric armor (AFA). Samples of both non-exposed (NE) and UV, MW and UV+MW exposed AFA, were subjected to ballistic tests against 0.380-caliber ammunition. The results of UV and UV+MW exposed samples revealed sensible macromolecular alterations, due to the scission of the polymeric chain by the processes of hydrolysis and photolysis, causing oxidation on the surface and breaking of the crystalline domains inside the aramid fiber. There was also a decrease in the crystallinity of the polyaramid macromolecular chain, being more severe after exposure to simple MW. However, no changes were observed in the thermal behavior of the AFA. The ballistic behavior was significantly affected by the weathering simulation conditions. The damage caused in the AFA by the ballistic impact was comparable within all groups exposed to degradation conditions. Practically, the same trauma, 28.2–32.1 mm and the same number, two (2), of perforated layers were observed for all exposed groups. These common ballistic results were less favorable than those of 25.7 mm and one layer, respectively, for the non-exposed AFA. The penetration traumas remained below the standard 44 mm lethal limit.
