Surface Modification of PVC Membranes Using Fluorothiophenol Compounds

The controlled chemical surface modification of PVC films by means of three fluoride aromatic compounds, 4-fluoro thiophenol, 3,4-difluorothiophenol and penta fluorothiophenol is reported. To obtain information about the surface selectivity of the reactions, the degree of modification of the polymer across the film was determined by depth profiling carried out using confocal Raman microscopy. It is shown that the gradient of the modification degree and the surface selectivity depend on the relationship between the rate constants of the substitution reaction and the diffusion process of the reactant. Therefore it is function of reaction time, temperature and the proportion of solvent/non-solvent used for the reaction.