Configurational entropy effect for conductivities of solid polymer electrolytes

Poly(itaconic acid) esters with oligo(ethylene oxide) side chains can form amorphous solid solutions with LiClO4 and NaClO4. Many research groups have examined AC ionic conductivities of these polymer/salt mixtures as a funct ion of side-chain length and salt concentration. We propose a model to inte rpret these experimental data based on a configurational entropy consisting of three kinds of entropy such as a mixing of polymer and salt ions, a dis orientation of polymers, and a drop of chain flexibility (or increase of T- g) with salt concentrations. Quantitative description according to the prop osed model is presented. (C) 1999 John Wiley & Sons, Inc.