Effects of coronands on ionic conductivities of complexes of poly[2-(4-vinylphenoxy)-2,4,4,6,6-penta(methoxyethoxyethoxyethoxy)cyclotriphosphazene] with LiClO4

The effects of coronands such as crown ether and azacrown on the conductivity of complexes of LiClO₄ with poly[2-(4-vinylphenoxy)-penta(methoxyethoxyethoxyethoxy)cyclotriphosphazene] [poly(STEP)] were investigated. The extent of T_g elevation of poly(STEP)-LiClO₄ with 18-crown-6 was comparable to that of the poly(STEP)-LiClO₄ system. A similar behavior was observed for the system containing 12-crown-4. However, the increase in T_g values is considerably suppressed when tetraazacyclotetradecane with methoxyethoxy group as a side arm (MTAC) is used. All of the additives are effective to improve the conductivity, and the maximum conductivities of 10⁻⁴ S/cm at 30°C and 10⁻³ S/cm at 90°C have been achieved for the complex of the poly(STEP)-LiClO₄-MTAC system with Li⁺/O = 0.06, which are 3.5–7 times higher than those of poly(STEP)-LiClO₄ complexes. From the behaviors of T_g elevation and the conductivity, the role of the coronands for the conduction of the multi-armed poly(STEP)-LiClO₄ system is discussed. © 1996 John Wiley & Sons, Inc.