Model calculations concerning the membrane potential and ionic fluxes
in weak amphoteric polymer membranes have been presented and the resul
ts were compared with recent experimental data obtained with a membran
e which contains succinyl chitosan as ampholyte and poly(vinyl alcohol
) as supporting matrix. The ion transport through the membrane has bee
n described with the aid of the Nernst-Planck equations, and the resul
ts obtained explain satisfactorily the observed experimental trends in
broad ranges of pH and electrolyte concentration. Also, the model pre
dictions concerning the membrane isoelectric point may be useful for t
he analysis of future experiments. (C) 1997 Elsevier Science Ltd.