Cargando…

Optothermal Switching of Cholesteric Liquid Crystals: A Study of Azobenzene Derivatives and Laser Wavelengths

The laser-initiated thermal (optothermal) switching of cholesteric liquid crystals (CLCs) is characterized by using different azobenzene (Azo) derivatives and laser wavelengths. Under 405-nm laser irradiation, Azo-doped CLCs undergo phase transition from cholesteric to isotropic. No cis-to-trans pho...

Descripción completa

Detalles Bibliográficos
Autores principales: Huang, Tai-Chieh, Chen, Yen-Yu, Chu, Chih-Chien, Hsiao, Vincent K. S.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5512900/
https://www.ncbi.nlm.nih.gov/pubmed/28793552
http://dx.doi.org/10.3390/ma8095293
_version_ 1783250548531658752
author Huang, Tai-Chieh
Chen, Yen-Yu
Chu, Chih-Chien
Hsiao, Vincent K. S.
author_facet Huang, Tai-Chieh
Chen, Yen-Yu
Chu, Chih-Chien
Hsiao, Vincent K. S.
author_sort Huang, Tai-Chieh
collection PubMed
description The laser-initiated thermal (optothermal) switching of cholesteric liquid crystals (CLCs) is characterized by using different azobenzene (Azo) derivatives and laser wavelengths. Under 405-nm laser irradiation, Azo-doped CLCs undergo phase transition from cholesteric to isotropic. No cis-to-trans photoisomerization occurs when the 405-nm laser irradiation is blocked because only a single laser is used. The fast response of Azo-doped CLCs under the on–off switching of the 405-nm laser occurs because of the optothermal effect of the system. The 660-nm laser, which cannot be used as irradiation to generate the trans–cis photoisomerization of Azo, is used in Anthraquinone (AQ)-Azo-doped CLCs to examine the optothermal effect of doped Azo. The results show that the LC-like Azo derivative bearing two methyl groups ortho to the Azo moiety (A4) can greatly lower the clearing temperature and generate large amount of heat in AQ-A4-doped CLCs.
format Online
Article
Text
id pubmed-5512900
institution National Center for Biotechnology Information
language English
publishDate 2015
publisher MDPI
record_format MEDLINE/PubMed
spelling pubmed-55129002017-07-28 Optothermal Switching of Cholesteric Liquid Crystals: A Study of Azobenzene Derivatives and Laser Wavelengths Huang, Tai-Chieh Chen, Yen-Yu Chu, Chih-Chien Hsiao, Vincent K. S. Materials (Basel) Article The laser-initiated thermal (optothermal) switching of cholesteric liquid crystals (CLCs) is characterized by using different azobenzene (Azo) derivatives and laser wavelengths. Under 405-nm laser irradiation, Azo-doped CLCs undergo phase transition from cholesteric to isotropic. No cis-to-trans photoisomerization occurs when the 405-nm laser irradiation is blocked because only a single laser is used. The fast response of Azo-doped CLCs under the on–off switching of the 405-nm laser occurs because of the optothermal effect of the system. The 660-nm laser, which cannot be used as irradiation to generate the trans–cis photoisomerization of Azo, is used in Anthraquinone (AQ)-Azo-doped CLCs to examine the optothermal effect of doped Azo. The results show that the LC-like Azo derivative bearing two methyl groups ortho to the Azo moiety (A4) can greatly lower the clearing temperature and generate large amount of heat in AQ-A4-doped CLCs. MDPI 2015-09-11 /pmc/articles/PMC5512900/ /pubmed/28793552 http://dx.doi.org/10.3390/ma8095293 Text en © 2015 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Huang, Tai-Chieh
Chen, Yen-Yu
Chu, Chih-Chien
Hsiao, Vincent K. S.
Optothermal Switching of Cholesteric Liquid Crystals: A Study of Azobenzene Derivatives and Laser Wavelengths
title Optothermal Switching of Cholesteric Liquid Crystals: A Study of Azobenzene Derivatives and Laser Wavelengths
title_full Optothermal Switching of Cholesteric Liquid Crystals: A Study of Azobenzene Derivatives and Laser Wavelengths
title_fullStr Optothermal Switching of Cholesteric Liquid Crystals: A Study of Azobenzene Derivatives and Laser Wavelengths
title_full_unstemmed Optothermal Switching of Cholesteric Liquid Crystals: A Study of Azobenzene Derivatives and Laser Wavelengths
title_short Optothermal Switching of Cholesteric Liquid Crystals: A Study of Azobenzene Derivatives and Laser Wavelengths
title_sort optothermal switching of cholesteric liquid crystals: a study of azobenzene derivatives and laser wavelengths
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5512900/
https://www.ncbi.nlm.nih.gov/pubmed/28793552
http://dx.doi.org/10.3390/ma8095293
work_keys_str_mv AT huangtaichieh optothermalswitchingofcholestericliquidcrystalsastudyofazobenzenederivativesandlaserwavelengths
AT chenyenyu optothermalswitchingofcholestericliquidcrystalsastudyofazobenzenederivativesandlaserwavelengths
AT chuchihchien optothermalswitchingofcholestericliquidcrystalsastudyofazobenzenederivativesandlaserwavelengths
AT hsiaovincentks optothermalswitchingofcholestericliquidcrystalsastudyofazobenzenederivativesandlaserwavelengths