Evolution of the thin photo-oxidation layer of an epoxy matrix during artificial photo-ageing

In previous papers the photo-chemical degradation of a bisphenol A epoxy re sin cross-linked with the hardener methyltetrahydrophthalic anhydride was s tudied by ATR FT-IR spectrophotometry and by X-ray analysis. The analyses c onfirmed the presence of a thin photo-oxidation layer at the surface of the material. After the establishment period, the layer and the ablation of th e organic matrix evolve spatially at a constant rate. From these results an d from the IR absorbency evolution of a v(O--H) vibration measured through thin films, the spatial distribution of the bond corresponding to this vibr ation was calculated as a contribution to the evolution analysis of the pho to-oxidation layer during photo-ageing.