| 학회 |
한국고분자학회 |
| 학술대회 |
2022년 봄 (04/06 ~ 04/08, 대전컨벤션센터) |
| 권호 |
47권 1호 |
| 발표분야 |
콜로이드 및 분자조립 부문위원회 |
| 제목 |
Effect of Positional Isomers on Photochemical and Optical Properties of Trigonal Azobenzene Chromophores |
| 초록 |
The two trigonal hydroxy azobenzene chromophores with methoxy substituent at 1,3 and 1,4 position (3mMeOAz, 3pMeOAz) have been synthesized. Their physical and optical properties were studied in addition to analyze the effect of positional isomer on spectroscopic and external stimulus response. Although the resulting compounds have the same molecular weight, they occupy different physical properties such as color, physical state and melting temperature. 3pMeOAz show dark grey colored light-flake in solid state while 3mMeOAz has scarlet red colored powder state. Consecutively, more planar para compound exhibits melting at 250 ℃ and meta shows at 279 ℃ as it has denser physical state. Moreover, the optical properties were examined by UV/Vis absorption and fluorescence spectra, Optical microscope (OM), Fluorescence optical microscope (FOM) and Scanning electron microscope (SEM). Intriguingly, 3mMeOAz has better UV light response with about trans/cis=92/8% by 360 min of UV light exposure whereas 3pMeOAz shows no photoisomerization under external stimulus exposure. The absorption spectrum of 3pMeOAz is red shifted because of longer π conjugated system whereas 3mMeOAz shows higher in fluorescence intensity in both solution and aggregation states and that was confirmed by the FOM. The nanofibers of 3mMeOAz in DMF-H2O solvent system exhibit intense red emission by green light excitation. One dimensional fibers and helical structures were assembled in the DMF-H2O and CHCl3-MeOH solvent systems by hydrogen bonding and π-π stacking interaction of the trigonal core and the periphery existing moieties. |
| 저자 |
Pyae Myat Phyo Thu1, 박상혁2, 한민아3
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| 소속 |
1Department of Chemistry, 2Kongju National Univ./Department of Chemistry Education, 3Kongju National Univ. |
| 키워드 |
positional isomers; one-dimensional self-assemblies
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| E-Mail |
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