SOLVATOCHROMIC STUDY OF WATER SORPTION IN POLYMER-FILMS

A solvatochromic method was used to characterize the water sorption be havior of polymer films. Four different dyes were dissolved in various solid polymers and the relative water vapor pressure in the atmospher e was changed. Evaluated solvatochromic parameters depended not only o n the amount of sorbed water but also on the kind of polymer. A linear correlation between the E(T)(30) value and Taft's multiparameter was confirmed in both the dried and the water sorbed polymers. The correla tion equation was almost identical to that obtained by other researche rs in liquid solvents. These results suggest that the dissolved dyes b ehave as indicators of microenvironmental changes in the solid polymer film. (C) 1997 John Wiley & Sons, Inc.