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New Advanced Liquid Crystalline Materials Bearing Bis-Azomethine as Central Spacer
In this study, a homologous series of novel liquid crystalline compounds bearing the bis-azomethine central linkage (–CH=N-N=CH–), namely ((1E,1′E)-hydrazine-1,2-diylidenebis(methanylylidene))bis(4,1-phenylene) dialkanoate (In), was synthesized, and the mesophase and thermal properties were investig...
Autores principales: | , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2022
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8953589/ https://www.ncbi.nlm.nih.gov/pubmed/35335586 http://dx.doi.org/10.3390/polym14061256 |
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author | Alamro, Fowzia S. Ahmed, Hoda A. Bedowr, Noha S. Khushaim, Muna S. El-atawy, Mohamed A. |
author_facet | Alamro, Fowzia S. Ahmed, Hoda A. Bedowr, Noha S. Khushaim, Muna S. El-atawy, Mohamed A. |
author_sort | Alamro, Fowzia S. |
collection | PubMed |
description | In this study, a homologous series of novel liquid crystalline compounds bearing the bis-azomethine central linkage (–CH=N-N=CH–), namely ((1E,1′E)-hydrazine-1,2-diylidenebis(methanylylidene))bis(4,1-phenylene) dialkanoate (In), was synthesized, and the mesophase and thermal properties were investigated theoretically and experimentally. The molecular structures of the prepared compounds were determined using elemental analysis, NMR, and FT-IR spectroscopy. The mesophase transitions were detected by differential scanning calorimetry (DSC), and the mesophases were identified using polarized optical microscopy (POM). The results indicated that the derivative with the shortest length (I5) was purely nematogenic, while the other homologues (I9 and I15) possessed SmC mesophases. The optimal geometrical structures of the investigated group were derived theoretically. The estimated results demonstrated that all homologues were mesomorphic, and their type depended on the length of the terminal chains. Computations based on density functional theory (DFT) were used to explain the experimental data. The calculated dipole moment, polarizability, thermal energy, and molecular electrostatic potential all showed that it was possible to predict the mesophase type and stability, which varied according to the size of the molecule. |
format | Online Article Text |
id | pubmed-8953589 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2022 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-89535892022-03-26 New Advanced Liquid Crystalline Materials Bearing Bis-Azomethine as Central Spacer Alamro, Fowzia S. Ahmed, Hoda A. Bedowr, Noha S. Khushaim, Muna S. El-atawy, Mohamed A. Polymers (Basel) Article In this study, a homologous series of novel liquid crystalline compounds bearing the bis-azomethine central linkage (–CH=N-N=CH–), namely ((1E,1′E)-hydrazine-1,2-diylidenebis(methanylylidene))bis(4,1-phenylene) dialkanoate (In), was synthesized, and the mesophase and thermal properties were investigated theoretically and experimentally. The molecular structures of the prepared compounds were determined using elemental analysis, NMR, and FT-IR spectroscopy. The mesophase transitions were detected by differential scanning calorimetry (DSC), and the mesophases were identified using polarized optical microscopy (POM). The results indicated that the derivative with the shortest length (I5) was purely nematogenic, while the other homologues (I9 and I15) possessed SmC mesophases. The optimal geometrical structures of the investigated group were derived theoretically. The estimated results demonstrated that all homologues were mesomorphic, and their type depended on the length of the terminal chains. Computations based on density functional theory (DFT) were used to explain the experimental data. The calculated dipole moment, polarizability, thermal energy, and molecular electrostatic potential all showed that it was possible to predict the mesophase type and stability, which varied according to the size of the molecule. MDPI 2022-03-21 /pmc/articles/PMC8953589/ /pubmed/35335586 http://dx.doi.org/10.3390/polym14061256 Text en © 2022 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article Alamro, Fowzia S. Ahmed, Hoda A. Bedowr, Noha S. Khushaim, Muna S. El-atawy, Mohamed A. New Advanced Liquid Crystalline Materials Bearing Bis-Azomethine as Central Spacer |
title | New Advanced Liquid Crystalline Materials Bearing Bis-Azomethine as Central Spacer |
title_full | New Advanced Liquid Crystalline Materials Bearing Bis-Azomethine as Central Spacer |
title_fullStr | New Advanced Liquid Crystalline Materials Bearing Bis-Azomethine as Central Spacer |
title_full_unstemmed | New Advanced Liquid Crystalline Materials Bearing Bis-Azomethine as Central Spacer |
title_short | New Advanced Liquid Crystalline Materials Bearing Bis-Azomethine as Central Spacer |
title_sort | new advanced liquid crystalline materials bearing bis-azomethine as central spacer |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8953589/ https://www.ncbi.nlm.nih.gov/pubmed/35335586 http://dx.doi.org/10.3390/polym14061256 |
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