Impedance spectra of free standing polyaniline membranes were recorded in t
he symmetric and the asymmetric cell configuration. The polyaniline membran
es were made by solution-casting of chemically polymerised polyaniline. The
impedance spectra are discussed according to a model of parallel ionic and
electronic conduction paths with capacitive and resistive coupling. Furthe
rmore the ion exchange behaviour of the membranes was studied. (C) 1999 Pub
lished by Elsevier Science Ltd. All rights reserved.