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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2013/03/02 17:58:29」(JST)

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A material is called lyotropic if it forms liquid crystal phases upon the addition of a solvent. Historically the term was used to describe materials composed of amphiphilic molecules. Such molecules comprise of an ionic or non-ionic hydrophilic head-group which is attracted to water, and attached to a hydrophobic group which is repelled by water. Typical hydrophobic groups are saturated or unsaturated hydrocarbon chains. Examples of amphiphilic compounds are the salts of fatty acids; phospholipids. Many simple amphiphiles are used as detergents. Lyotropic liquid crystal phases in these materials are formed by a process of self-assembly that is driven by the hydrophobic effect.

Lyotropic liquid crystal phases are formed on the dissolution of amphiphilic molecules of a material in a solvent. There are several different type of lyotropic liquid crystal structures. Each of these different types has a different extent of molecular ordering within the solvent matrix.

The term lyotropic has also been applied to the liquid crystalline phases that are formed by certain polymeric materials, particularly those consisting of rigid rod-like macromolecules, when they are mixed with appropriate solvents. Examples are suspensions of rod-like viruses as the Tobacco Mosaic Virus as well as man-made colloidal suspensions of non-spherical colloidal particles. Other examples include DNA and Kevlar, which dissolves in sulfuric acid to give a lyotropic phase. It is noted that in these cases the solvent acts to lower the melting point of the materials thereby enabling the liquid crystalline phases to be accessible. These liquid crystalline phases are closer in architecture to thermotropic liquid crystalline phases than to the conventional lyotropic phases. In contrast to the behaviour of amphiphilic molecules, the lyotropic behaviour of the rod-like molecules does not involve self-assembly.

English Journal

Liquid crystal-based emulsions: progress and prospects.

Alam MM, Aramaki K.Author information Department of Chemistry, Faculty of Science and Engineering, Saga University.AbstractRecent progress in lyotropic liquid crystal (LC)-based emulsions over the last few years has been reviewed. The tuning parameters for the formation, stability, rheology and transparency of LC-based emulsions are addressed. Recent applications of LC-based emulsions to the fabrication of dual meso/macroporous materials are also included.
Journal of oleo science.J Oleo Sci.2014 Feb 5;63(2):97-108. Epub 2014 Jan 14.
Recent progress in lyotropic liquid crystal (LC)-based emulsions over the last few years has been reviewed. The tuning parameters for the formation, stability, rheology and transparency of LC-based emulsions are addressed. Recent applications of LC-based emulsions to the fabrication of dual meso/mac
PMID 24420064

Atomic distribution and structural evolution of mesostructured PtRu nanoparticles electrodeposited on a microemulsion lyotropic liquid-crystalline template probed using EXAFS and XANES.

Chen SA, Liang YC, Lu KT, Pao CW, Lee JF, Lin TL, Chen JM.Author information National Synchrotron Radiation Research Center (NSRRC), 101 HsinAnn Road, 30076 Hsinchu, Taiwan. ktlu@nsrrc.org.tw jmchen@nsrrc.org.tw.AbstractMesostructured PtRu nanoparticles were electrochemically reduced from their metallic salts directed by a hexagonally packed microemulsion lyotropic liquid-crystalline (MLLC) template. We investigated the structural evolution and atomic distribution of the MLLC-templated mesoporous PtRu nanoparticles (NPs) after electroreduction for varied duration using X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy, complemented by energy-dispersive X-ray spectroscopy (EDS) and field-emission transmission electron microscopy (FE-TEM). The XANES data at the Ru L2,3 and Pt L3 edges show predominantly metallic states of Ru and Pt in the PtRu NPs upon electroreduction. The reduction of Ru(3+) ions in RuCl3 into Ru atoms involves intermediate RuCl-containing complexes. A more rapid reduction of Pt precursors and a release of Ru atoms from Ru precursors in two steps upon electroreduction resulted in aggregation into PtRu nanoparticles, featuring a Pt-rich core, a Ru-rich shell and a varied alloy extent of Ru, deduced from EXAFS data. The complementary results provide insight into the mechanism of growth and atomic distribution of mesostructured PtRu bimetallic nanoparticles from the use of the MLLC-type templates.
Physical chemistry chemical physics : PCCP.Phys Chem Chem Phys.2014 Feb 5;16(9):3939-45. doi: 10.1039/c3cp53201a.
Mesostructured PtRu nanoparticles were electrochemically reduced from their metallic salts directed by a hexagonally packed microemulsion lyotropic liquid-crystalline (MLLC) template. We investigated the structural evolution and atomic distribution of the MLLC-templated mesoporous PtRu nanoparticles
PMID 24346132

Chiral symmetry breaking and surface faceting in chromonic liquid crystal droplets with giant elastic anisotropy.

Jeong J, Davidson ZS, Collings PJ, Lubensky TC, Yodh AG.Author information Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104.AbstractConfined liquid crystals (LC) provide a unique platform for technological applications and for the study of LC properties, such as bulk elasticity, surface anchoring, and topological defects. In this work, lyotropic chromonic liquid crystals (LCLCs) are confined in spherical droplets, and their director configurations are investigated as a function of mesogen concentration using bright-field and polarized optical microscopy. Because of the unusually small twist elastic modulus of the nematic phase of LCLCs, droplets of this phase exhibit a twisted bipolar configuration with remarkably large chiral symmetry breaking. Further, the hexagonal ordering of columns and the resultant strong suppression of twist and splay but not bend deformation in the columnar phase, cause droplets of this phase to adopt a concentric director configuration around a central bend disclination line and, at sufficiently high mesogen concentration, to exhibit surface faceting. Observations of director configurations are consistent with Jones matrix calculations and are understood theoretically to be a result of the giant elastic anisotropy of LCLCs.
Proceedings of the National Academy of Sciences of the United States of America.Proc Natl Acad Sci U S A.2014 Feb 4;111(5):1742-7. doi: 10.1073/pnas.1315121111. Epub 2014 Jan 21.
Confined liquid crystals (LC) provide a unique platform for technological applications and for the study of LC properties, such as bulk elasticity, surface anchoring, and topological defects. In this work, lyotropic chromonic liquid crystals (LCLCs) are confined in spherical droplets, and their dire
PMID 24449880

Japanese Journal

Photopatterned Coatable Polarizer for Flexible Display

Yoon So-Ra,Yang Hye-Jin,Jeong Kwang-Un,Lee Myong-Hoon
Jpn J Appl Phys 52(5), 05DB12-05DB12-4, 2013-05-25
… We present a novel method to photopattern a thin-film polarizer from a photosensitive lyotropic chromonic liquid crystal (LCLC) solution based on perylene dye. …
NAID 150000106895

Multi-length scale evaluation of the temperature-tunable mechanical properties of a lyotropic mesophase

Lee Sungwon,Seifert Sonke,Firestone Millicent A
Polymer journal 45(2), 179-187, 2013-02-00
NAID 40019560304

Structural Rheology of Smectic Liquid Crystalline Phase

藤井修治
日本レオロジー学会誌 40(5), 229-237, 2013
… The rheological properties of layered systems such as a thermotropic smectic liquid crystal and surfactant lyotropic lamellar phase are studied from the viewpoint of structural rheology. …
NAID 130003362512