Molecular structure and relaxation properties of poly(ethyleneglycol)-ionene systems

Results of investigations of acoustic relaxation in anionically conducting low molecular weight ionene-poly(ethylene glycol) (PEG) complexes of various ionene contents are presented. Analysis of the results of the ultrasonic measurements shows that the acoustic spectra measured involve two dispersion regions at frequencies f1 and f2 in the order of increasing frequency. In accordance with data obtained for pure PEG, these dispersions are related to a conformation transition and the structural relaxation process, respectively. The relaxation time of the latter decreases with increasing temperature and increases with increasing ionene concentration. The essential increase in sound velocity occurs already at the smallest ionene content (10%), together with characteristic changes in the relaxation strength r2 of the structural relaxation process and sharp drop in f1 and f2. These results provide evidence for significant decrease in the compressibility of the PEG-ionene solutions in comparison to that of the pure polymeric solvent . This can be explained as the result of increasing level of intermolecular interaction in the solutions in comparison to the pure solvent. (author)