The temperature dependence of the complex shear modulus, G = G' + jG', of poly(pyrrole) anion and cation exchanging films was investigated in aqueous solutions as a function of potential in the temperature interval 15-50 degrees C. Both G' and G' decrease with increasing temperature for anion exchangers and remain constant for cation exchangers. This effect is explained in terms of free volume effects and glass temperature variation due to the presence of trapped large surfactant anions in the cation exchanging and mobile small anions in the anion exchanging films. (c) 2007 Elsevier B.V. All rights reserved.