Synthesis and mesomorphic properties of non-symmetric liquid crystalline dimers containing azobenzene groups
Four novel nonsymmetric dimers containing azobenzene mesogenic groups were synthesized. The nonsymmetric dimers compounds namely, ethyl 4-[(4-{4-(4-((4-nitrophenyl)diazenyl)phenoxy)alkyloxy}phenyl)diazenyl]benzoate were obtained from the alkylation of ethyl 4-[(4-(4-bromoalkyloxy)phenyl)diazenyl]ben...
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Taylor & Francis
2009
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| Online Access: | http://psasir.upm.edu.my/id/eprint/16941/ http://psasir.upm.edu.my/id/eprint/16941/1/Synthesis%20and%20mesomorphic%20properties%20of%20non.pdf |
| _version_ | 1848843101997629440 |
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| author | Rahman, Md Lutfor Asik, Jahimin Kumar, Sandeep Silong, Sidik Ab. Rahman, Mohamad Zaki |
| author_facet | Rahman, Md Lutfor Asik, Jahimin Kumar, Sandeep Silong, Sidik Ab. Rahman, Mohamad Zaki |
| author_sort | Rahman, Md Lutfor |
| building | UPM Institutional Repository |
| collection | Online Access |
| description | Four novel nonsymmetric dimers containing azobenzene mesogenic groups were synthesized. The nonsymmetric dimers compounds namely, ethyl 4-[(4-{4-(4-((4-nitrophenyl)diazenyl)phenoxy)alkyloxy}phenyl)diazenyl]benzoate were obtained from the alkylation of ethyl 4-[(4-(4-bromoalkyloxy)phenyl)diazenyl]benzoate with 4-[(4-nitrophenyl)diazenyl]phenol. The mesomorphic properties of the compounds were determined by DSC and polarizing optical microscopy. The first member of the series was nonliquid crystalline while all other homologues display nematic and smectic A phases. The trans-azobenzene groups of the dimers display a high-intensity –* transition at about 365nm and a low-intensity n–* transition at around 465 nm, therefore, photochromism can be achieved by the introduction of the azo linkage to the dimeric liquid crystalline molecules.
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| first_indexed | 2025-11-15T08:09:41Z |
| format | Article |
| id | upm-16941 |
| institution | Universiti Putra Malaysia |
| institution_category | Local University |
| language | English English |
| last_indexed | 2025-11-15T08:09:41Z |
| publishDate | 2009 |
| publisher | Taylor & Francis |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | upm-169412015-10-30T02:30:56Z http://psasir.upm.edu.my/id/eprint/16941/ Synthesis and mesomorphic properties of non-symmetric liquid crystalline dimers containing azobenzene groups Rahman, Md Lutfor Asik, Jahimin Kumar, Sandeep Silong, Sidik Ab. Rahman, Mohamad Zaki Four novel nonsymmetric dimers containing azobenzene mesogenic groups were synthesized. The nonsymmetric dimers compounds namely, ethyl 4-[(4-{4-(4-((4-nitrophenyl)diazenyl)phenoxy)alkyloxy}phenyl)diazenyl]benzoate were obtained from the alkylation of ethyl 4-[(4-(4-bromoalkyloxy)phenyl)diazenyl]benzoate with 4-[(4-nitrophenyl)diazenyl]phenol. The mesomorphic properties of the compounds were determined by DSC and polarizing optical microscopy. The first member of the series was nonliquid crystalline while all other homologues display nematic and smectic A phases. The trans-azobenzene groups of the dimers display a high-intensity –* transition at about 365nm and a low-intensity n–* transition at around 465 nm, therefore, photochromism can be achieved by the introduction of the azo linkage to the dimeric liquid crystalline molecules. Taylor & Francis 2009 Article PeerReviewed application/pdf en http://psasir.upm.edu.my/id/eprint/16941/1/Synthesis%20and%20mesomorphic%20properties%20of%20non.pdf Rahman, Md Lutfor and Asik, Jahimin and Kumar, Sandeep and Silong, Sidik and Ab. Rahman, Mohamad Zaki (2009) Synthesis and mesomorphic properties of non-symmetric liquid crystalline dimers containing azobenzene groups. Phase Transitions: A Multinational Journal, 82 (3). pp. 228-239. ISSN 0141–1594 Dimers - Analysis Dimers - Properties Azo compounds 10.1080/01411590802642406 English |
| spellingShingle | Dimers - Analysis Dimers - Properties Azo compounds Rahman, Md Lutfor Asik, Jahimin Kumar, Sandeep Silong, Sidik Ab. Rahman, Mohamad Zaki Synthesis and mesomorphic properties of non-symmetric liquid crystalline dimers containing azobenzene groups |
| title | Synthesis and mesomorphic properties of non-symmetric liquid crystalline dimers containing azobenzene groups |
| title_full | Synthesis and mesomorphic properties of non-symmetric liquid crystalline dimers containing azobenzene groups |
| title_fullStr | Synthesis and mesomorphic properties of non-symmetric liquid crystalline dimers containing azobenzene groups |
| title_full_unstemmed | Synthesis and mesomorphic properties of non-symmetric liquid crystalline dimers containing azobenzene groups |
| title_short | Synthesis and mesomorphic properties of non-symmetric liquid crystalline dimers containing azobenzene groups |
| title_sort | synthesis and mesomorphic properties of non-symmetric liquid crystalline dimers containing azobenzene groups |
| topic | Dimers - Analysis Dimers - Properties Azo compounds |
| url | http://psasir.upm.edu.my/id/eprint/16941/ http://psasir.upm.edu.my/id/eprint/16941/ http://psasir.upm.edu.my/id/eprint/16941/1/Synthesis%20and%20mesomorphic%20properties%20of%20non.pdf |