Influence of montmorillonite nano-dispersion on polystyrene photo-oxidation

UV photo-oxidative degradation of polystyrene/montmorillonite nanocomposites (PS/o-MMTs) and microcomposite (PS/Na/MMT), obtained via in situ bulk polymerization, has been studied in accelerated conditions. Imidazolium or standard alkylammonium surfactants were used to modify MMT. The chemical modification resulting from photo-oxidation has been followed using infrared spectroscopy The rate of photo-oxidation of PS/o-MMT and PS/Na/MMT was faster than that of pristine PS. The results suggest that the photo-oxidative instability could be related to the degree of exfoliation and then to the presence of catalytic active sites on the MMT layer Surface. (C) 2008 Elsevier Ltd. All rights reserved.