Following the First Steps of UV Degradation of High Density Polyethylene by Fluorescence Spectroscopy
Ultraviolet radiation is one of the major factors that affect weathering of polymers. Indeed, diffusion of oxygen containing groups [-C-O, C=O and C(=O)O-] into the molecular chains of polymers is particularly enhanced by UV irradiation in air, thus entailing structural and chemical changes such as polymeric chain breaking, cross-linking and oxidation. The goal of this study is to predict the photo-chemical ageing of polymers upon UV radiation through a non destructive method: fluorescence spectroscopy. In the case of high density polyethylene (HDPE) the addition of fluorophore is required to make it fluorescent. The spectral features of fluorescence are very sensitive to the interactions between the excited molecules and the matrix. In this way, Fourier-Transform InfraRed spectrophotometry (FTIR) and Differential Scanning calorimetry (DSC) have been employed to correlate the fluorescence spectra with the degradation phenomena.
A. Agüero, J.M. Albella, M.P. Hierro, J. Phillibert and F.J. Pérez Trujillo
L. Douminge et al., "Following the First Steps of UV Degradation of High Density Polyethylene by Fluorescence Spectroscopy", Defect and Diffusion Forum, Vols. 289-292, pp. 741-746, 2009