• Journal of the Korean Applied Science and Technology
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• v.16 no.4
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• pp.281-286
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• 1999

We carried out this subject to observe photoisomerization using 8A5H and phospholipid(DLPC) containing azobenzene group which has reversible to cis-trans by light irradiation. We investigated the photoisomerization and property of the monolayer film on quartz substrate prepared by the mixture of 8A5H and phospholipid deposited using Langmuir-Blodgett(LB) method. It was found that the absorption spectrum of the 8A5H and phospholipid LB monolayer was induced to photoisomerization by alternate light irradiation. And the absorbance of both the solution of mixtures of 8A5H-phospholipid and LB film was reversibly changed by the acid-base exposure and alternate temperatures.

• Bulletin of the Korean Chemical Society
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• v.20 no.12
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• pp.1421-1427
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• 1999

4-Hydroxy-4'-methoxyazobenzene and 4-hydroxy-4'-cyanoazobenzene were synthesized from phenol with p-anisidine and p-aminobenzonitrile through a diazotization reaction, respectively. They were reacted with 2-chloroethanol, 2-(2-chloroethoxy)ethanol, or 2-[2-(2-chloroethoxy)ethoxy]ethanol to produce six kinds of new mesogenic alcohols having an azobenzene group that is sensitive to the ultraviolet. Twelve kinds of new photoresponsive monomers with two symmetrical mesogens were prepared by the reaction of the mesogenic alcohols with fumaric acid or maleic acid through a Mitsunobu reaction. The resulting monomers have different length of flexible ethyleneoxy spacer tethered to azobenzene group. The length of the spacer affected their thermal stability, solubility, and phase transition temperature. Structures of the monomers were identified by FT-IR and ¹H-NMR spectra. Their phase transition temperatures and thermal stability were also investigated by a differential scanning calorimetry (DSC) and a thermogravimetric analysis (TGA). From an optical polarizing microscopy, all the prepared monomers except fumarate-1 and maleate-1 were found to show enantiotropic liquid crystallinity with a smectic texture like focal-conic, fan-shaped, and batonnet textures.

• Proceedings of the Korean Fiber Society Conference
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• 1986.06a
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• pp.15-15
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• 1986

• Journal of Photoscience
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• v.1 no.1
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• pp.61-62
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• 1994

Upon exposure to daylight, trans-2,2'-dimethoxyazobenzene isomerized to give a equilibrium mixture of 70% cis and 30% trans isomer. The high photo-steady concentration of cis isomer is discussed compared with that of azobenzene.

• Proceedings of the Optical Society of Korea Conference
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• 2004.07a
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• pp.106-107
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• 2004

• Proceedings of the Korean Fiber Society Conference
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• 1991.06b
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• pp.46-46
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• 1991

• KSBB Journal
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• v.15 no.4
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• pp.375-379
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• 2000

Alginate derivatives possessing various lengths of alkyl amine (C8, C12, C16) chain were prepared by oxidation followed by reductive amination of alginate and the products were characterized by spectral analysis. The surface tension critical micelle concentration (c. m. c) and solubility of a hydrophobic compound azobenzene were examined. Series of synthesized alginate-derived polymeric surfactants(APSs) reduced the surface tension. The dissolving capacity of APSs toward azobenzene was about half that of SDS. In order to investigate the capacity of metal adsorption Co and Pb were selected as a representative metal. The overall removal efficiency of APSs were high compared with that of alginate at pH 3.5 and 7 respectively. Major mechanism of the heavy metal removal is the complex of metal with carboxyl group.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.29 no.6
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• pp.571-575
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• 2016

Photo responsive polymer(PRP) is well known for its photo deformation under UV light, and goes back to its original shape in visible light due to the photoisomerization of the azobenzene inside the PRP. In this paper, dynamic study of the vibration in PRP is discussed. In order to predict photo-deformation of the PRP a multiscale modeling is introduced which covers quantum level photo excitation, microscopic morphology, and macroscopic deformation of the PRP. A simple 1D beam model is introduced to model dynamic bending behavior of the PRP. Through fast Fourious transformation analysis, we identify that vibration frequency of the PRP can be controlled by light polarization angle.

• Bulletin of the Korean Chemical Society
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• v.28 no.10
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• pp.1821-1823
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• 2007

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1543-1546
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• 2013