NEW MACROMOLECULES FOR SOLID POLYMERIC ELECTROLYTES

The polyphosphazene MEEP, [NP(OCH2CH2OCH2CH2OCH3)(2)](n), was first re ported 12 years ago as a significant advance in the design of solid po lymer electrolytes (P. M. Blonsky,D. F. Shriver, P. E. Austin and H. R Allcock, J. Am. Chem.;Soc. 106, 6854 (1984)) [1]. Since that time, mo re than 30 new polymers have been synthesized in our laboratory, which build on the basic structure and theory developed for MEEP. The new p olymers possess a phosphazene backbone, which is the basis of the mole cular flexibility, with a variety of different alkyl ether and alkoxy side groups. The ionic conductivity of these polymers in the presence of lithium triflate has been studied as a function of the different po lymer side groups. Several systems that improve on the properties of M EEP have been identified. The behaviour of selected polymers in operat ing rechargeable batteries has also been investigated. (C) 1998 Publis hed by Elsevier Science Ltd. All rights reserved.