• 공업화학
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• 제20권1호
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• pp.75-79
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• 2009

아닐린 단량체(monomer)의 화학적 중합시 사슬성장의 핵심생성구간에서 아닐린 이합체(dimer, p-aminodiphenylamine)의 몰 비율을 조절하여 반응용액에 첨가함으로써 분자량(Mw, 20000~10000) 조절이 가능한 폴리아닐린을 합성 하였다. 중합반응의 개시로 부터 측정된 반응시간에 따른 open-circuit potential 측정결과 첨가된 이합체의 몰수가 증가할수록 중합속도가 빨라짐을 확인하였다. 첨가된 이합체의 몰수가 증가할수록 UV/Vis. 측정결과 합성된 폴리아닐린의 흡수띄가 단파장으로 이동하였으며, GPC 측정결과 분자량이 감소하는 것을 볼 수 있었다.

• Carbon letters
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• 제10권1호
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• pp.14-18
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• 2009

We measured the degree of macrodispersion of the various single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) using UV-VIS-NIR absorption spectroscopy. CNTs were dispersed with SDS of 2 wt % in deionized water using the homogenizer and then were further centrifugated at 6000 g for 10 min. The degree of macrodispersion, expressed by $D_m({\lambda})=A_a({\lambda})/A_b({\lambda})^*100$ (%), where ${\lambda}$ is the wavelength and $A_a({\lambda})$ and $A_b({\lambda})$ are the absorbance of the sample after and before centrifugation, respectively. In the case of MWCNTs, we evaluated the degree of macrodispersion by the average degree of macrodispersion ($D_m({\lambda})$) between 1000 and 1200 nm. The degree of macrodispersion of SWCNTs was evaluated at the wavelength in which van Hove singularity-related transition regions were excluded, i.e., the range was chosen between ${E_{11}}^S$ and ${E_{22}}^S$ peaks. We have estimated six samples with the same method. The standard deviation of each sample was lower than 5. Therefore, we presented a reliable evaluation method for the macrodispersion of CNTs for standardization.

• 통합자연과학논문집
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• 제2권2호
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• pp.73-77
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• 2009

Silyl-containing tetraphenylsilole, 1,1-bis(trisilyl)tetraphenylsilole, has been synthesized from the reaction of dichlorotetraphenylsilole and dichlorotrisilane and characterized by using NMR spectroscopy. Bis(trisilyl)tetraphenylsilole exhibits an unusual optical property and its optical property was characterized by UV-vis and fluorescence spectroscopy. Absorption wavelength maxima of bis(trisilyl)tetraphenylsilole was 380 nm. Bis(trisilyl)tetraphenylsilole displayed an emission band at 530 nm with an excitation wavelength of 380 nm.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2276-2280
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• 2013

The accurate prediction of vertical excitation energies is very important for the development of new materials in the dye and pigment industry. A time-dependent density functional theory (TD-DFT) approach coupled with 22 different exchange-correlation functionals was used for the prediction of vertical excitation energies in the halogenated copper phthalocyanine molecules in order to find the most appropriate functional and to determine the accuracy of the prediction of the absorption wavelength and observed spectral shifts. Among the tested functional, B3LYP functional provides much more accurate vertical excitation energies and UV-vis spectra. Our results clearly provide a benchmark calibration of the TD-DFT method for phthalocyanine based dyes and pigments used in industry.

• 통합자연과학논문집
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• 제2권4호
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• pp.270-274
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• 2009

Organometallic polymers containing spirosilole unit have been interested, since spirosiloles has a unique optical and electronic properties. New functionalized spirosiloles (2,5-dibromo-3,4,6,7,8,9-hexaphenylspirosilole, DBHPSS) have been synthesized from the reduction of bis(1,1-phenylethynyl)-2,3,4,5-tetraphenylsilole with lithium naphthalenide for the possible applications in optics. DBHPSS has been characterized by $^1H$-NMR, fluorescence, and UV-vis absorption spectroscopy and elemental analysis. Bis(phenylethynyl)tetraphenylsilole displays an emission maxima at 490 nm with an excitation wavelength of 380 nm. However, DBHPSS displays an emission maxima at 550 nm with an excitation wavelength of 420 nm.

• 한국전기전자재료학회논문지
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• 제28권5호
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• pp.314-319
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• 2015

In this research, we focused on the development of cy3 dye with high thermal stability and good solubility for LCD color filter. Cy3 dyes were prepared through the synthetic procedure of two steps. The synthesized cy3 dyes were characterized by using NMR, FT-IR, UV/Vis spectroscopy, and TGA. These cy3 dyes showed maximum absorption wave length (${\lambda}_{max}$) in the range of 549~555 nm in UV/Vis spectrum. And we confirmed that solubility characteristics and thermal stability of cy3 dyes were dependent on the structure of counter cation. Cy3 dyes with methyl counter cation and ethyl counter cation have good solubility in organic solvents such as chloroform, ethanol, and PGME. Moreover, Cy3 dye with ethyl counter cation gave excellent thermal stability in TGA thermograms. And Cy3 dye with ethyl counter cation showed good result in photoresist film test.

• 접착 및 계면
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• 제23권2호
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• pp.39-43
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• 2022

디스플레이, 태양전지와 같이 전기를 빛으로, 또는 빛을 전기로 변환시켜주는 광전자소자는 효율 향상을 위하여 빛의 거동 제어가 매우 중요하다. 즉, OLED의 경우 내부 빛 제어를 통해 더 많은 빛이 외부로 나갈 수 있도록 유도해 줄 때 발광효율을 향상시킬 수 있으며, 외부 빛 제어를 통해 광흡수층에서의 광경로를 증대시킬 경우 태양전지의 에너지 변환효율을 증가시킬 수 있다. 본 연구에서는 이러한 광거동 제어가 가능한 구조로서 주름구조에 대한 연구를 진행하였으며 응력 해소 시간을 제어하여 구조의 주기와 높이를 독립적으로 제어하고자 하였다. 주기와 높이의 변화가 광거동에 어떠한 영향을 미치는지 살펴보기 위하여 일정한 주기에서 높이 변화 및 유사한 높이에서 주기 변화에 따른 자외선/가시광선 분광분석(UV/Vis spectroscopy)을 실시하였으며 구조의 종횡비가 클수록 직진광의 비율이 낮고 분산광의 비율이 높음을 확인하였다. 이를 통해 광경로 변화 및 광경로 증가를 위하여 큰 종횡비의 주름구조가 요구됨을 확인할 수 있었다.

• 한국전기전자재료학회논문지
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• 제33권3호
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• pp.194-200
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• 2020

Perylene bisimide derivatives are developed for red organic phosphor because of their advantages, such as excellent luminous efficiency and high thermal stability. Despite these advantages, they have poor solubility characteristics in organic solvents and short emission wavelength as red organic phosphor for hybrid light-emitting diodes (LEDs). In this study, we prepared terrylene bisimide using a coupling reaction and swallow-tail imide group, which has excellent solubility. The structures and properties of swallow-tail terrylene bisimide (9C) were analyzed using ¹H-nuclear magnetic resonance (¹H-NMR), Fourier-transform infrared (FT-IR), UV/Vis spectroscopy, and thermal gravimetric analysis (TGA). The maximum absorption wavelength of (9C) in the UV/Vis spectrum was 647 nm, and the maximum emission wavelength was 676 nm. In the TGA, (9C) demonstrated good thermal stability with less than 5 wt% weight loss up to 415℃. In the solubility test, (9C) has a good solubility of more than 5 wt% in chloroform and dichloromethane. When the compounds (9C) were mixed with PMMA (polymethly methacrylate), the films showed peaks at 680 nm in the PL spectra. The results verify the suitability of (9C) as a red organic phosphor for hybrid LEDs.

• 한국염색가공학회지
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• 제13권3호
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• pp.165-171
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• 2001

In this study, UV/vis. spectra of color solution extracted from onion shell and dyeing properties of polyamide fibers such as wool, silk, and nylon were investigated. Also, the effect of mordanting on wash fastness and light fastness was Investigated. The amount of colors extracted was increased with extracting temperature and time. The wavelength of maximum absorption of onion shell extract corresponds to flavonol peak and quercetin peak. Also, spectra of color solution were shifted to longer wavelength at higher pH values. It appeared that the optimum condition of the dyeing of wool, nylon, and silk fabrics with onion shell extract was $60^\circ{C}$ , 30min, and pH 4.0 of dyed bath. Surface colors of the dyed fabrics were different according to the used mordants: Al and Cr mordanted fabrics were dyed in yellowish colors, Cu mordanted fabric in greenish color, Sn mordanted fabric in orange color, and Fe mordanted fabric in khaki color. The mordanting was effective at improving wash fastness and light fastness.

• 통합자연과학논문집
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• 제2권4호
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• pp.289-292
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• 2009

Perchlorosilanes are useful precursors for the synthesis of hydrosilanes for the fabrication of electronic devices such as silicon thin-film transistors and silicon nanoparticles. For this solution process, requirements of precursors applicable to solution process are relatively low volatile and soluble in common organic solvents. In this work, the decaphenylcyclopentasilane has been obtained from the reaction of the lithium wire and dichlorodiphenylsilane. The reaction of decaphenylcyclopentasilane with lewis acid catalyst, HCl/$AlCl_3$, gives the perchlorocyclopentasilane. Decaphenylcyclopentasilane exhibits an unusual optical property. Its optical property was characterized by UV-vis and fluorescence spectroscopy. Absorption wavelength maxima for the decaphenylcyclopentasilane was 272 nm. Decaphenylcyclopentasilane displayed an emission band at 741 nm with excitation wavelength of 272 nm.