Synthesis and characterisation of ternary polymer electrolytes with enhanced miscibility and high conductivity

This paper reports the synthesis of amorphous polymer electrolytes. Polymer-salt complexes in the ternary system were prepared by mixing two polymers, namely poly(oxyethylene) and poly(oxypropylene glycol), with sodium iodide. This three component system is represented on a ternary pseudophase diagram. The ternary compositions are completely amorphous in a certain composition range and the composition POE-12%POPG-NaI with O/Na = 10 exhibited record high conductivity of 2 x 10(-4) (Ohm cm)(-1) at ambient temperature. Formation of the amorphous electrolyte and the enhanced miscibility of the polymers were analysed using differential scanning calorimetry, X-ray diffraction and ionic conductivity studies. The cation was found to play a major role in enhancing the miscibility of the polymers.