ANION DYNAMICS AND CONDUCTIVITY IN GLASSY POLYELECTROLYTES - A 2-DIMENSIONAL SOLID-STATE NMR-STUDY

For the first time, the dynamics of the anions of ionically conducting amorphous polyelectrolytes have been investigated by applying one- an d two-dimensional solid state C-13-NMR techniques. The glass transitio n in cationic polyelectrolytes of the type ''ionenes'' is characterize d by the softening of a network formed by N+-cations which are linked by organic segments. However, the counterions are already mobile below the glass transition. About 40 K below T(g), the anion dynamics are f ound to be spatially isotropic on the NMR timescale, which is in good agreement with results obtained by dielectric spectroscopy. The ionic conductivity in the glassy state can be described as thermally activat ed anion transport. Its high activation energy indicates a cooperative character of the anion motion.