Structure, Properties, and Na+ Transport Membrane of Polyelectrolyte Complexes Consisting of Glycol Chitosan and Poly(vinyl sulfate)

Abstract

Abstract Glycol chitosan (GC) was allowed to react with poly(vinyl sulfate) (PVSK) to form many different water-insoluble polyelectrolyte complexes (PECs) in aqueous solution at various hydrogen ion concentrations. According to elemental analyses, IR spectroscopy, and solubilities of PECs, molecular structures of each PEC depend on [H+]. This result is attributable to change with [H+] in the degree of dissociation and conformation of GC and PVSK. PEC membranes were made by casting solutions of all kinds of PECs, and transport phenomena through a membrane of the PEC prepared in a solution of 4v/v% HCl were investigated under various conditions. The transport ratio of Na+ and the electric potential difference between the left and right sides of the membrane were measured, with a result that the higher value the membrane potential difference was long allowed to maintain, the higher the transport ratio became. According to this result, the driving force of transport is dependent on the membrane potential, Donnan potential and diffusion potential, between both sides of the membrane. The Cl− exclusion (Donnan exclusion), however, is small due to the small cation-exchange capacity, so that the membrane potential difference is caused to decrease rather rapidly by Cl− permeation.