ANION SOLVATION EFFECTS IN POLYMER-ELECTROLYTES - NASCN AND LISCN IN PEO-400 AND IN PEG-400

Infrared spectra in the ''CN-stretch'' region of the SCN- anion, for N aSCN and LiSCN, dissolved in polyethylene oxide dimethylether (PEO-400 ) of average molar mass 400, show dramatic differences from the infrar ed spectra of the same electrolytes dissolved in polyethylene oxide gl ycol (PEG-400) of average molar mass 400. The differences are attribut ed to anion solvation by the -OH end of the PEG polymers. Similar comp arison of the molar refraction R of the two electrolytes dissolved in the two solvents, also shows dramatic differences in the values and co ncentration dependence of the R(NaSCN) and of R(LiSCN) between the two polymer solutions. These differences are also attributed to anion H-b onding solvation by PEG-400. The different molecular status of the abo ve electrolytes in the two solvents, should be considered, when planni ng their use as ion transport media in polymer-electrolyte batteries.