Mesophase study of pure and doped cyanobiphenyl liquid crystals with salen-type systems
| Autor: | Zoulikha Khouba, Tayeb Benabdallah, Amal Bendahou, Ulrich Maschke |
|---|---|
| Přispěvatelé: | Unité Matériaux et Transformations - UMR 8207 (UMET), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut National de la Recherche Agronomique (INRA), Institut de Chimie du CNRS (INC)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Ecole Nationale Supérieure de Chimie de Lille (ENSCL), Université des sciences et de la Technologie d'Oran Mohamed Boudiaf [Oran] (USTO MB), Institut National de la Recherche Agronomique (INRA)-Ecole Nationale Supérieure de Chimie de Lille (ENSCL)-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Université de Lille, ENSCL, CNRS, INRA, Unité Matériaux et Transformations - UMR 8207 [UMET], Université des sciences et de la Technologie d'Oran Mohamed Boudiaf [Oran] [USTO MB] |
| Jazyk: | angličtina |
| Rok vydání: | 2018 |
| Předmět: |
Phase transition
Materials science Guest host 02 engineering and technology 010402 general chemistry 01 natural sciences [SPI.MAT]Engineering Sciences [physics]/Materials chemistry.chemical_compound Liquid crystal Polymer chemistry General Materials Science [SPI.GPROC]Engineering Sciences [physics]/Chemical and Process Engineering ComputingMilieux_MISCELLANEOUS Schiff base Doping Condensation Mesophase General Chemistry [CHIM.MATE]Chemical Sciences/Material chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 0104 chemical sciences [CHIM.POLY]Chemical Sciences/Polymers chemistry Salicylaldehyde 0210 nano-technology |
| Zdroj: | Liquid Crystals Liquid Crystals, 2018, Liquid Crystals, 89, pp.1-12. ⟨10.1080/02678292.2018.1435827⟩ Liquid Crystals, 2018, Liquid Crystals, 45 (9), pp.1312-1323. ⟨10.1080/02678292.2018.1435827⟩ |
| ISSN: | 0267-8292 1366-5855 |
| DOI: | 10.1080/02678292.2018.1435827⟩ |
| Popis: | International audience; In the current study, two salenSchiff base ligands derived from the condensation of ethylendiamine on salicylaldehyde and 5-chlorosalicylaldehyde, namely, N,N’-bis( salicylidene)ethylene-diamine(L1) and N,N’-bis(5-chlorosalicylidene)ethylene-diamine (L2)as well as two of their iron(III) and nickel(II) complexes were prepared, and then used as doping agents of two thermotropic liquid crystals of cyanobiphenyle type, namely, 4-cyano-4’-n-pentyl (5CB) and 4′-n-octyl-4-cyano-biphenyl (8CB). The study of the mesophase of pure and doped liquid crystals was carried out by UV-visible spectroscopy equipped with a heating compartment for precise temperature control, differential scanning calorimetry and polarized optical microscopy. The characteristic transition temperatures, nematic-isotropic, TNI, and/or smectic-nematic, TSN, of liquid crystals based systems were measured and then compared to those of the literature concerning pure 5CB and 8CB. Optical microscopy has shown the existence of Schlieren and focal conic textures of the nematic and smectic states respectively, both of pure and doped liquid crystals. The homogeneity of the obtained guest-host systems was proven by the linear evolution of their transition temperatures as function of the concentration in solute, with correlation factors near to unity. |
| Databáze: | OpenAIRE |
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