title: Thermotropic and lyotropic behaviour of new liquid-crystalline materials with different hydrophilic groups: synthesis and mesomorphic properties.
abstract: Several new calamitic liquid-crystalline (LC) materials with flexible hydrophilic chains, namely either hydroxy groups or ethylene glycol units, or both types together, have been synthesized in order to look for new functional LC materials exhibiting both, thermotropic and lyotropic behaviour. Such materials are of high potential interest for challenging issues such as the self-organization of carbon nanotubes or various nanoparticles. Thermotropic mesomorphic properties have been studied by using polarizing optical microscopy, differential scanning calorimetry and X-ray scattering. Four of these nonchiral and chiral materials exhibit nematic and chiral nematic phases, respectively. For some molecular structures, smectic phases have also been detected. A contact sample of one of the prepared compounds with diethylene glycol clearly shows the lyotropic behaviour; namely a lamellar phase was observed. The relationship between the molecular structure and mesomorphic properties of these new LCs with hydrophilic chains is discussed.
authors.affiliation: Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague, Czech Republic.
authors.forename: Alexej
authors.initials: A
authors.lastname: Bubnov
authors.forename: Miroslav
authors.initials: M
authors.lastname: Kašpar
authors.forename: Věra
authors.initials: V
authors.lastname: Hamplová
authors.forename: Ute
authors.initials: U
authors.lastname: Dawin
authors.forename: Frank
authors.initials: F
authors.lastname: Giesselmann
keywords: contact cell preparation; hydrophilic chain; lamellar phase; lyotropic liquid crystal; thermotropic liquid crystal