Characteristics of a complex of ethylene oxide-phosphate copolymer with LiClO4 as a polymer electrolyte

Methoxy phosphoryl chloride was reacted with polyethylene glycol of molecular weight of 300 to produce a linear ethylene oxide-phosphate copolymer. The polymer is characterized and the ionic conductivity of the complex with LiClO4, measured by means of frequency response analyzer, is in the range of 4 × 10−5 S/cm at room temperature when the mole ratio of the ethoxy group to the salt is 60:1. The polymer shows glass transition temperature of −61°C which jumps to −48°C when mixed with the salt by the mole ration of 60:1. A further increase in the weight of the salt shows little change in glass transition temperature. It is noted that the ionic conductivity changes little with an increase of temperature when the mole ratio of the polymer and the salts is 60:1.