Abstract
Changes in wettability and surface structure of Siloxane polymers under vacuum ultraviolet (VUV) irradiation (wavelength 147nm) and storage in water were investigated by contact angle measurements and ATR FTIR spectroscopy. The increase of wettability observed after VUV irradiation is associated with the formation of CO and OH polar groups in the polymer surface layer. Storage in water and air media of VUV treated samples leads to the increase of contact angle which could be related to dissolution of small highly polar fragments in water or to decomposition of unstable products of photooxidation. Correlation of contact angle changes with the water content in the polymer surface layer observed during storage in water for untreated samples leads to the conclusion that in this case water sorbtion is the major path to wettability changes.
