What are the effects of prolonged UV exposure on the molecular weight of polyethylene?
Prolonged exposure to ultraviolet (UV) radiation significantly affects the molecular weight of polyethylene, a widely used polymer. UV rays break the polymer chains through photo-oxidation, leading to chain scission and a reduction in molecular weight. This degradation process weakens the material's mechanical properties, such as tensile strength and flexibility. Factors like UV intensity, exposure duration, and additives in polyethylene influence the rate of degradation. Understanding these effects is crucial for improving polyethylene's durability in outdoor applications. Proper stabilization techniques, such as UV inhibitors, can mitigate these adverse effects and extend the material's lifespan.
