Premium
Ionic conductivity and side chain relaxation in polyglutamates having oligo(ethylene oxide) chains
Author(s) -
Watanabe Masayoshi,
Aoki Sei,
Sanui Kohei,
Ogata Naoya
Publication year - 1993
Publication title -
polymers for advanced technologies
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.61
H-Index - 90
eISSN - 1099-1581
pISSN - 1042-7147
DOI - 10.1002/pat.1993.220040218
Subject(s) - side chain , ethylene oxide , ionic conductivity , ionic bonding , materials science , glass transition , conductivity , electrolyte , oxide , polymer , polymer chemistry , relaxation (psychology) , ion , chemistry , organic chemistry , composite material , social psychology , psychology , electrode , copolymer , metallurgy
New polymer hosts to form polymer electrolytes, poly[methoxy‐oligo(ethylene oxide)‐ L ‐glutamate] (PMnEOG, n = 1, 2, 3 and 7, n stands for the number of ethylene oxide units), have been prepared in order to study the correlation between the side chain relaxation and the ionic conductivity of PMnEOG/LiClO 4 complexes. The main chains of PMnEOGs form a rigid rod‐like structure (α‐helix structure) in the solid state both in the absence and the presence of LiClO 4 . The oligo(ethylene oxide) side chains begin to be mobile at temperatures lower than 0°C, while the rigid main chains do not move up to 100°C. The side chains show a preferential solvation of incorporated LiClO 4 . The ionic conductivity of 10 −7 −10 −6 S/cm is attained in PM3EOG/LiClO 4 and PM7EOG/LiClO 4 complexes at room temperature, where only the short side chain motion contributes to the ionic transport. The temperature dependencies of the side chain relaxation time and ionic conductivity increase with increasing the side chain length when the temperature dependencies are normalized by the temperatures based on the glass transition temperatures of the side chains, which indicates strong cooperation between the side chain motion and the ion transport. The possibility of fast ion transport by short side chain relaxation is discussed.