POLY(ETHYLENE OXIDE) POLY(2-VINYLPYRIDINE)/LITHIUM PERCHLORATE BLENDSAS SOLID POLYMER ELECTROLYTES - COMPOSITION PROPERTY STRUCTURE INTERRELATIONSHIP/

Poly(ethylene oxide) (MW 600,000)/poly(2-vinylpyridine) (MW 200,000)/L iClO4 blends have been prepared by the solution blending process. The ionic conductivities of the blends containing lower weight fractions ( 15, 17.5, 20, and 22.5%) of poly(2-vinylpyridine) initially increases as the salt content is increased, reaches a maximum at an ethylene oxi de/Li+ mole ratio of 10 and decreases as the salt content is further i ncreased. Blends, which have higher weight fractions of poly(2-vinylpy ridine) (25 and 35%) display different electric behavior, i.e., the io nic conductivity continously increased as the salt content is increase d to an ethylene oxide/Li+ mole ratio of 2. Thermal, Li-7 solid-state NMR and semiempirical MNDO molecular orbital studies indicate that thi s contrasting behavior may be explained by the structure and ratios of the solvates (mixed solvate or homosolvate) of LiClO4 present in the blends. (C) 1995 John Wiley and Sons, Inc.