Degradation behavior of ultra-high molecular weight polyethylene fibers under artificial accelerated weathering

This work aims to study the aging behavior of ultra-high molecular weight polyethylene (UHMWPE) fibers under xenon arc radiation. The correlation between structure and properties was analyzed by Fourier transform infrared spectroscopy, differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA) and small angle X-ray scattering (SAXS). Both physical and chemical aging were observed. Carbonyl compounds were generated from the chain scission after radiation. The carbonyl index linearly increased with aging time. Both DMTA and DSC revealed that the crystal defects emerged after aging. Synchrotron SAXS was employed to characterize such structure. A model based on the information derived from SAXS is proposed. The results indicate that tensile strength is strongly affected by defects.