scholarly journals Design of Ionic Liquid Crystals Forming Normal-Type Bicontinuous Cubic Phases with a 3D Continuous Ion Conductive Pathway

Crystals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 309 ◽  
Author(s):  
Takahiro Ichikawa ◽  
Yui Sasaki ◽  
Tsubasa Kobayashi ◽  
Hikaru Oshiro ◽  
Ayaka Ono ◽  
...  

We have prepared a series of pyridinium-based gemini amphiphiles. They exhibit thermotropic liquid–crystalline behavior depending on their alkyl chain lengths and anion species. By adjusting the alkyl chain lengths and selecting suitable anions, we have obtained an ionic amphiphile that exhibits a normal-type bicontinuous cubic phase from 38 °C to 12 °C on cooling from an isotropic phase. In the bicontinuous cubic liquid–crystalline assembly, the pyridinium-based ionic parts align along a gyroid minimal surface forming a 3D continuous ionic domain while their ionophobic alkyl chains form 3D branched nanochannel networks. This ionic compound can form homogeneous mixtures with a lithium salt and the resultant mixtures keep the ability to form normal-type bicontinuous cubic phases. Ion conduction measurements have been performed for the mixtures on cooling. It has been revealed that the formation of the 3D branched ionophobic nanochannels does not disturb the ion conduction behavior in the ionic domain while it results in the conversion of the state of the mixtures from fluidic liquids to quasi-solids, namely highly viscous liquid crystals. Although the ionic conductivity of the mixtures is in the order of 10–7 S cm–1 at 40 °C, which is far lower than the values for practical use, the present material design has a potential to pave the way for developing advanced solid electrolytes consisting of two task-specific nanosegregated domains: One is an ionic liquid nano-domain with a 3D continuity for high ionic conductivity and the other is ionophobic nanochannel network domains for high mechanical strength.

1979 ◽  
Vol 34 (11) ◽  
pp. 1535-1541 ◽  
Author(s):  
Alois Villiger ◽  
Arthur Boiler ◽  
Martin Schadt

Abstract Liquid Crystals, Cyclohexyl-phenyl-pyrimidines, Dicyclohexyl-pyrimidines The synthesis and mesomorphic properties of three new classes of cyano-substituted cyclohexyl-phenyl-and dicyclohexyl-pyrimidines are reported. The compounds are colourless, chemically and photochemically stable and have wide nematic mesophases. The thermal compatibility of the new compounds with other nematic liquid crystals is excellent. The large static positive dielectric anisotropics are shown to depend strongly on the position and number of hydrogenated rings as well as on the alkyl chain lengths within a homologous series. The reported bulk viscosities vary considerably among homologues. Hydrogenating the ring adjacent to the cyano end group causes η to increase, whereas a considerable viscosity reduction compared to nonhydrogenated homologues was found by hydrogenating the ring adjacent to the alkyl end group. The measured refractive indices of the new compounds are comparable to those of biphenyls.


2021 ◽  
Vol 11 (21) ◽  
pp. 10347
Author(s):  
Melina S. Weber ◽  
Margit Schulze ◽  
Giuseppe Lazzara ◽  
Antonio Palumbo Piccionello ◽  
Andrea Pace ◽  
...  

The synthesis and characterization of a new class of 1,2,4-oxadiazolylpyridinium as a cationic scaffold for fluorinated ionic liquid crystals is herein described. A series of 12 fluorinated heterocyclic salts based on a 1,2,4-oxadiazole moiety, connected through its C(5) or C(3) to an N-alkylpyridinium unit and a perfluoroheptyl chain, differing in the length of the alkyl chain and counterions, has been synthesized. As counterions iodide, bromide and bis(trifluoromethane)sulfonimide have been considered. The synthesis, structure, and liquid crystalline properties of these compounds are discussed on the basis of the tuned structural variables. The thermotropic properties of this series of salts have been investigated by differential scanning calorimetry and polarized optical microscopy. The results showed the existence of an enantiotropic mesomorphic smectic liquid crystalline phase for six bis(trifluoromethane)sulfonimide salts.


RSC Advances ◽  
2014 ◽  
Vol 4 (24) ◽  
pp. 12476-12481 ◽  
Author(s):  
Xinjiao Wang ◽  
Michelle Sternberg ◽  
Florian T. U. Kohler ◽  
Berthold U. Melcher ◽  
Peter Wasserscheid ◽  
...  

New ionic liquids and ionic liquid crystalline materials with custom-tailored properties were synthesized based on long-alkyl-chain-derivatized 1,3-dialkylimidazolium salts.


2020 ◽  
pp. 1-10
Author(s):  
Aikebaier Reheman ◽  
Shuangying Hu ◽  
Lianjun Cao ◽  
Danhua Xie ◽  
Guiyang Yan ◽  
...  

2017 ◽  
Vol 66 (3) ◽  
pp. 63-74
Author(s):  
Anna Drzewicz ◽  
Marzena Tykarska ◽  
Magdalena Żurowska

The infrared spectra were registered for series of three-ring liquid crystalline esters, differing in the structure of alkyl chain, in the substitution of benzene ring by fluorine atoms and in the type of helicoidal structure in the chiral smectic CA phase with antiferroelectric properties. The influence of molecular structure on the shift of signals coming from carbonyl group, located in the rigid core, was observed. Keywords: liquid crystals, helicoidal structure, chiral smectic CA phase, antiferroelectric crystalline phase, infrared spectroscopy


2020 ◽  
Vol 8 (37) ◽  
pp. 12902-12916 ◽  
Author(s):  
Mohamed Alaasar ◽  
Silvio Poppe ◽  
Yu Cao ◽  
Changlong Chen ◽  
Feng Liu ◽  
...  

The photoisomerizable functional azobenzene unit is organized in synclinic hexatic, anticlinic smectic and bicontinuous cubic liquid crystalline phases as well as in achiral or mirror symmetry broken isotropic network liquids.


2017 ◽  
Vol 8 (10) ◽  
pp. 1689-1698 ◽  
Author(s):  
Yu-Dong Zhang ◽  
Jing Ping ◽  
Qi-Wei Wu ◽  
Hong-Bing Pan ◽  
Xing-He Fan ◽  
...  

A block copolymer containing a liquid crystalline polymer and a poly(ionic liquid) self-assembles and can be used as a solid electrolyte.


2020 ◽  
Vol 301 ◽  
pp. 112369 ◽  
Author(s):  
Yanxing Zheng ◽  
Jiwei Wang ◽  
Xinqiao Tang ◽  
Lei Zhang ◽  
Fanbao Meng

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