|Title:||Mesomorphic glass-forming ionic complex composed of a pair of cholesterol phthalate and 1-Cn-3-methylimidazolium: Phase transition and enthalpy relaxation behavior|
SUGIMURA, Kazuki https://orcid.org/0000-0003-2394-1420 (unconfirmed)
TERAMOTO, Yoshikuni https://orcid.org/0000-0003-3850-3570 (unconfirmed)
|Author's alias:||杉村, 和紀|
|Journal title:||Polymer Journal|
|Abstract:||Ionic complexes consisting of a mesogenic cholesterol derivative and 1-alkyl (Cn)-3-methylimidazolium (CnMim) (n = 6–18) were prepared from ethanol solutions containing an equimolar mixture of cholesterol hydrogen phthalate (CHP) and 1-Cn-3-methylimidazolium hydroxide; the imidazolium hydroxide was obtained by anion exchange of 1-Cn-3-methylimidazolium bromide. The complex samples, termed [CnMim][CHP], were examined to evaluate their thermal transition patterns. Excluding the two samples (n = 6, 8) that showed no definite ordered phase, the complexes with n ≥ 10 formed a cholesteric (n = 10, 12) or smectic (n = 14–18) mesophase in a considerably wide range of temperatures; this wide range reflects the additional thermotropic property of the salts of CnMim with longer alkyl chains. These fluid mesophases transformed into a mesomorphic vitreous solid without crystallization in a usual cooling process. For the glassy mesomorphic samples of selected complexes (n = 10, 18), the enthalpy relaxation behavior was followed as a function of the aging temperature and time, and the data were analyzed in terms of a Kohlrausch–Williams–Watts (KWW) type of stretched exponential equation. A very narrow distribution of relaxation times was observed for the “liquid crystalline glasses”, indicating the high uniformity of the relaxation mode.|
|Rights:||This is the accepted manuscript of the article, which has been published in final form at https://doi.org/10.1038/s41428-018-0047-5.|
This is not the published version. Please cite only the published version.
|Appears in Collections:||Journal Articles|
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