Studies on Ultraviolet-Triggered Chain Scission in Cotton: from Hydroxyls to Carbonyls

This work focuses on the degradation of fibers upon exposure to ultraviolet (UV) radiation. Physical changes in fibers following UV exposure were examined, and both polyamide (PA) and polyester (PET) fibers exhibited surface degradation when observed under scanning electron microscopy (SEM). UV radiation initiates photooxidative degradation, which leads to polymer chain scission, free radical formation, and a reduction in molecular weight. These processes deteriorate the mechanical properties of fibers and eventually render the materials unusable after an unpredictable period of exposure. This phenomenon, known as UV degradation, affects a wide range of natural and synthetic polymers, including rubbers, neoprene, and polyvinyl chloride (PVC). Prolonged UV exposure can cause fading, embrittlement, and loss of performance. When absorbed, UV energy excites photons within the polymer structure, generating free radicals that accelerate degradation, especially in the presence of catalyst residues. Since many pure plastics lack inherent UV resistance, their long-term durability is at serious risk, emphasizing the importance of protective measures in polymer applications.