Time-Dependent Environmental Degradation of Polymeric Fabrics

It is qualitatively understood and accepted that the mechanical integrity of polymeric webbing materials, such as those used in the construction of backpacks, tree stands, and other outdoor equipment, deteriorates due to outdoor exposure to sun’s UV radiation and the heat and moisture from the environment. Quantitative studies of these effects are rare and they have primarily been performed via accelerated tests conducted in laboratory settings. The purpose of this study was to develop a quantitative understanding of the effect of exposure time and dosage to outdoor environment, including solar radiation, heat, wet, and dry cycles, on polymer webbings materials. Three different common webbing materials—polypropylene, polyester, and nylon—were selected and subjected to up to 24 months of outdoor exposure, at one month increments. Following environmental exposure, each material was tested via standard tensile test to determine the load-deflection behavior of each material for different exposure periods, the results were compared with those of unexposed baseline materials. It was found that polypropylene had the greatest resistance to environmental degradation but also the lowest tensile strength, while polyester had the least resistance but the highest overall tensile strength.