A STUDY ON MOLECULAR-TRANSPORT OF ORGANIC ESTERS AND AROMATICS INTO VITON FLUOROPOLYMERS

Molecular transport of organic liquids into Viton fluoropolymers has b een investigated by a sorption-desorption gravimetric method. Diffusio n coefficients have been calculated from Fick's equation. The sorption -desorption results have been used to calculate the concentration prof iles by solving Fick's diffusion equation under suitable boundary cond itions. A numerical method based on the finite difference technique wa s also used to calculate the concentration profiles of liquids as a fu nction of sorption time and thickness of the Viton fluoropolymers. The dependence of sorption, desorption, diffusion, and permeation propert ies of the liquids on temperature showed a significant effect. The Arr henius activation parameters have been estimated for diffusion, permea tion, and sorption processes. The experimental and calculated results are discussed to study the type and nature of interactions between Vit on fluoropolymers and the solvent molecules. (C) 1997 John Wiley & Son s, Inc.