Evidence of dissolved ions and ion pairs in dilute poly(propylene oxide)salt solutions
Abstract To test previous interpretations of splitted Raman modes in terms of solvated “free” ions and ion pairs in polyether-salt complexes we have carried out Raman measurements of poly(propylene oxide) (PPO) containing MClO 4 and MCF 3 SO 3 ( M = Li or Na), respectively, from the low concentrations L : M = 1000 ( O : M is the oxygen to salt ratio) previously not investigated to the range O : M ≈ 30−5 in which most reported spectral measurements have been carried out.