Ion Conductivity of Comb Polysiloxane Polyelectrolytes Containing Oligoether and Perfluoroether Sidechains

Abstract
The ion conductivity has been studied in comb polyelectrolytes consisting of a polysiloxane backbone with oligoether and lithium-sulfonate terminating perfluoroether sidechains. The room-temperature conductivity was found to reach a maximum of 2.5×10−6S/cm2.5×10−6S/cm at 33 etheric oxygens per lithium ion. The cation mobility is coupled to the polymer segmental motion and is described by the Vogel-Tamman-Fulcher (VTF) equation. The mechanisms behind ion mobility are studied by means of the VTF parameters σ0,σ0, B, and T0.T0. In particular, the number of charge carriers as reflected in the parameter σ0σ0 is shown to strongly correlate with the conductivity maxima as a function of lithium ion concentration. © 2003 The Electrochemical Society. All rights reserved.