957336-90-2Relevant academic research and scientific papers
Columnar liquid-crystalline imidazolium salts. effects of anions and cations on mesomorphic properties and ionic conductivities
Yoshio, Masafumi,Ichikawa, Takahiro,Shimura, Harutoki,Kagata, Takayoshi,Hamasaki, Atsushi,Mukai, Tomohiro,Ohno, Hiroyuki,Kato, Takashi
, p. 1836 - 1841 (2007)
Two series of 1-methyl-3-[3,4,5-tris(alkyloxy)benzyl]imidazolium salts (1(n/X-); n = 8, 12, 16, and 18) and 1,2-dimethyl-3-[3,4,5- tris(dodecyloxy)benzyl]imidazolium salts (2(12/X-)) containing anions (X-), such as tetrafluoroborate, hexafluorophosphate, trifluoromethylsulfonate, and bis(trifluoromethylsulfonyl)imide, have been synthesized. The thermal properties of these salts were characterized by differential scanning calorimetry, polarizing optical microscopy, and X-ray diffraction. The salts form hexagonal columnar liquid-crystalline phases except for 1(8/X-) and 1(12/X-) containing CF3SO 3- and (CF3SO2)2N -, and 2(12/(CF3SO2)2N)-) which melt directly to isotropic ionic liquids. The clearing points show a decreasing trend with an increase in the size of anions. The ionic conductivities of 1(16/X-) forming columnar phases have been measured by using an alternating current impedance method. The conductivities depend on the nature of anions, suggesting that the predominant conduction mechanism is hopping and/or diffusion of anions in the columnar structures.
