Mesomorphism dependence on lateral substitution of functional groups and their position in series: 4(4′-n-alkoxy benzoyloxy)-3-chloro phenyl azo-2″-methoxy benzenes
| Autor: | A. V. Doshi, D. H. Patel, H. R. Prajapati |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Polarized light microscopy
Chemistry Stereochemistry Mesogen Mesophase 02 engineering and technology General Chemistry 010402 general chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences 0104 chemical sciences Crystallography Liquid crystal Phase (matter) Alkoxy group Molecule General Materials Science Thermal stability 0210 nano-technology |
| Zdroj: | Molecular Crystals and Liquid Crystals. 624:51-58 |
| ISSN: | 1563-5287 1542-1406 |
| DOI: | 10.1080/15421406.2015.1044156 |
| Popis: | Eleven homologues of the title series were synthesized. The methyl-to-pentyl derivatives are nonmesomorphic. The nematic mesophase commences from the sixth member of the series without any smectic phase. An odd–even effect in the nematic–isotropic transition curve is not observed. The nematic mesophase appeared as a threaded or a Schlieren-type texture as observed through a hot-stage polarizing microscope. The nematic–isotropic transition temperatures are between 89°C and 127°C with the mesomorphic range varying from 9°C to 44°C at the hexyl and tetradecyl derivative of the series, respectively. The nematic–isotropic transition curve initially rises and then falls in a normal manner as the series is ascended, but it abnormally rises beyond the 10th homologue. The series is enantiotropic nematic with a middle-ordered melting type. Analytical data support the structures of the molecules. The thermal stability and some other mesomorphic characteristics are compared with structurally similar homologou... |
| Databáze: | OpenAIRE |
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