A CAPILLARY CELL FOR MEASURING DIFFUSION-COEFFICIENTS OF ELECTROLYTE-SOLUTIONS IN POLYMERS

A new application of the open-ended conductimetric capillary cell for measuring mutual differential diffusion coefficients of aqueous electr olyte solutions in polymers is presented. Diffusion coefficients of so lutions of KCl, NaCl, and LiCl in some polymers (polyurethane (PU) foa m, polyvinyl alcohol (PVA) and poly-hydroxybutyrate (POxB)) have been measured to 298 K and prove the applicability of the cell to measure d iffusion coefficients in this kind of polymer-solvent-electrolyte syst em. The experimental diffusion coefficients are explained on the basis of a further flux caused by a perturbed equilibrium between adsorbed and free hydrated ions.