Premium
Measurement of anisotropic ion conduction in liquid crystalline states having polyether segments
Author(s) -
ItoAkita Kaori,
Nishioko,
Asai Yoshihiro,
Ohno Hiroyuki,
Ohtake Toshihiro,
Takamitsu Yasuyuki,
Kato Takashi
Publication year - 2000
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 - 10.1002/1099-1581(200008/12)11:8/12<529::aid-pat1>3.0.co;2-g
Subject(s) - materials science , homeotropic alignment , liquid crystal , ionic conductivity , phase (matter) , indium tin oxide , ethylene oxide , layer (electronics) , electrode , chemical engineering , composite material , organic chemistry , polymer , chemistry , optoelectronics , engineering , copolymer , electrolyte
Ion conductive layer of poly(ethylene oxide) (PEO) chain was constructed with the aid of the alignment of liquid crystalline molecules. The liquid crystal containing the PEO structure shows enantiotropic smectic phases from 20 to about 200 °C. This liquid crystalline molecule can stand perpendicularly and make homeotropic phase on comb‐shaped Au electrodes deposited on the glass substrate. Since the liquid crystal was in the single domain (homeotropic) only on glass and gold surfaces, the aligned oxyethylene unit in the liquid crystal should form quasi‐ion‐conductive‐layer which is parallel to the glass surface. The ionic conductivity parallel to the conducting layer of this liquid crystal containing lithium triflate was 10 −3 S/cm at 85 °C which was 10 3 times higher than that for multi‐domain phase observed on the indium tin oxide (ITO) electrodes. This value is quite high as that in highly viscous matrix. Such high ionic conductivity was only observed in the liquid crystal (smectic) phase, and it decreased at and above the isotropic temperature. In the isotropic phase, no successive and effective ion conductive layer existed resulting in the lower ionic conductivity. Copyright © 2000 John Wiley & Sons, Ltd.