• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.50-51
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• 2006

The nanofibrous scaffolds were obtained by co-electrospinning PHBV and collagen Type I in HIFP. The resulting fiber diameters were in the range between 300 and 600 nm. The nanofiber surfaces were characterized by ATR-FTIR, ESCA and AFM. The PHBV and collagen components of the PHBV-Col nanofibrous scaffold were biodegraded by PHB depolymerase and a collagenase Type I aqueous solution, respectively. It was found, from the cell-culture experiment, that the PHBV-Col nanofibrous scaffold accelerated the adhesion of the NIH 3T3 cell compared to the PHBV nanofibrous scaffold, thus showing a good tissue engineering scaffold.

• Journal of Electrochemical Science and Technology
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• 제11권1호
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• pp.41-49
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• 2020

In this study poly(carbazole) films deposited on stainless steel have been investigated as electrode material for supercapacitor applications. Poly(carbazole) films were electrodeposited using cyclic voltammetry in presence of lithium, sodium and tetrabutylammonium perchlorate salts. Poly(carbazole) films doped with perchlorate anions having different counter cations were characterized by SEM, ATR-FTIR and solid state conductivity measurements. Capacitive behaviours of PCz coated steel electrodes were tested by cyclic voltammetry, charge-discharge analysis and electrochemical impedance spectroscopy. It was found that counter cation of the dopant is significantly effective on the capacitive performance on the obtained PCz films and the PCz film synthesized from lithium perchlorate has the better capacitive performance than the poly(carbazole)s synthesized from sodium perchlorate and tetrabutylammonium perchlorate salts.

• Macromolecular Research
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• 제14권6호
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• pp.617-623
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• 2006

In order to achieve an oriental lacquer (OL) film with a thick consistency, UV-curable silicone acrylate (SA) was added to OL by a dual curing process. The addition of 5 wt% UV-curable SA to the OL fomulation enabled the preparation via a single drying step of a $77{\mu}m-thick$ film exhibiting excellent surface properties. FTIR-ATR was used to investigate the effect of UV-curable SA on the behavior of film formation during curing, and the relaxation behavior of the produced films was investigated by dielectric spectroscopy. Dielectric properties were measured in the frequency range $10^{-2}-10^5\;Hz$ at various temperatures between -100 and $200^{\circ}C$. The results demonstrated that OL modified by UV-curable SA has a higher glass transition temperature and stronger secondary relaxation at a lower temperature than the conventional OL system. The OL film modified with UV-curable SA was presumed to be harder at the surface and tougher than conventional OL film.

• 한국전기전자재료학회논문지
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• 제18권5호
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• pp.450-456
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• 2005

In this paper, the effect of adhesion properties of semiconductive-insulating interface layer of silicone rubber on electrical properties was investigated. The modifications produced on the silicone surface by oxygen plasma were accessed using ATR-FTIR, contact angle and Surface Roughness Tester. Adhesion was obtained from T-peel tests of semiconductive layer haying different treatment durations. In addition, ac breakdown test was carried out for elucidating the change of electrical property with duration of plasma treatment. From the results, the treatment in the oxygen plasma produced a noticeable increase in surface energy, which can be mainly ascribed to the creation of O-H and C=O. It is observed that adhesion performance was determined by surface energy and roughness level of silicone surface. It is found that at dielectric strength was increased with improving the adhesion between the semiconductive and insulating interface.

• Macromolecular Research
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• 제11권5호
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• pp.311-316
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• 2003

The kinetics of photoinitiated polymerization of dimethacrylate macromonomers have been studied to determine the diffusion-controlled reaction parameters using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). A predicted kinetic rate expression with a diffusion control factor was employed to estimate an effective rate constant and to define the reaction-controlled and diffusion-controlled regimes in the photopolymerization. An effective rate constant, k$_{e}$, can be obtained from the predicted kinetic rate expression. At the earlier stages of polymerization, the average values of kinetic rate constants do not vary during the reaction time. As the reaction conversion, $\alpha$, reaches the critical conversion, $\alpha$$_{c}$, in the predicted kinetic expression, the reaction becomes to be controlled by diffusion due to the restricted mobility of dimethacrylate macromonomers. A drop in value of effective rate constant causes a drastic decrease of reaction rate at the later stages of polymerization. By determining the effective rate constants, the reaction-controlled and diffusion-controlled regimes were properly defined even in the photopolymerization reaction system.m.m.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.173-176
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• 2000

In this paper, we investigated the surface degradation of HTV silicone rubber used for a polymeric insulator by UV irradiation. To study the surface ageing properties by W irradiation, we used the corona discharge charging and contact angle. Therefore, we observed the change of surface charge retention and decrease of surface hydrophobicity. Also, we discussed the chemical change in the surface range using the analytic equipment such as SEM, ATR-FTIR, ESCA. Therefore, it is found that the scissor of characteristic bonding and the reattachment of oxidant bonding was developed by UV rays radiation. As discussing the corona ischarge charging and the change of contact angle, it is found the effect of UV irradiation and the mechanism of chemical reaction

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1996년도 추계 학술발표회
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• pp.478-483
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• 1996

다관능성 에폭사이드 PPE(Polyglycerol Polyglycidyl Ether)를 양모섬유에 처리하였을 때 부가반응의 특성을 고찰하였다. 에폭사이드 PPE에 의한 부가반응이 촉매작용을 하는 NaSCN 존재하에서 이관능성 EGDE보다 높은 부가율을 얻을 수 있었다. 에폭사이드 부가반응은 고온에서 반응이 잘 일어나며 에폭사이드 처리욕의 pH는 반응 초기 급격히 상승했다가 이후 점차 초기 값까지 안정화된다. 처리한 양모섬유를 FTIR의 KBr-pellet법과 ATR법에 의해 분석하여 absorbance ratio를 비교하였을 때 부가반응은 표면으로의 그라프트 반응이 우세함을 알 수 있었으며 이러한 결과는 SEM 관측을 통하여 확인할 수 있었다. Performic acid/Ammonia solubility를 에폭사이드 처리 양모섬유에 적용하여 용해도 변화를 보았을 때 부가된 양이 많을수록 용해도 값이 감소하며 특히 15.6%를 중심으로 용해도 변화가 둔화되었다. 아미노산 분석으로 에폭사이드가 반응한 아미노산이 cystine임을 알 수 있었으며 단백질 사슬간에 가교반응이 이루어졌음을 확인할 수 있었다.

• 한국전기전자재료학회논문지
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• 제13권5호
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• pp.411-419
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• 2000

In this paper we have investigated the surface degradation by ultraviolet-irradiation in high-temperature vulcanized silicone rubber. Through the measurement of surface potential decay by corona-charging and of contact angle it is found that the change of surface electrostatic properties and the decrease of contact angle under UV-radiation. For the changes in micro-morphological and chemical structure of the UV-treated silicone rubber we utilized several analytical techniques such as SEM, ATR-FTIR,XPS. From this study it is shown that the chemical reactions(scissoring of side chain(S-$CH_3$) cross-linking and branching) occur on the surface of silicone rubber during the UV-irradiation. Also we obtained the results of the loss of low molecular weight chain by cross-linking and oxidation reaction.

• Journal of Electrochemical Science and Technology
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• 제12권3호
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• pp.365-376
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• 2021

Two arylamino substituted mercaptoimidazole derivatives namely 4,5-dimethyl-1-(phenylamino)-1H-imidazole-2(3H)-thione (I1) and 4,5- dimethyl-1-((p-chlorophenyl)amino)- 1H-imidazole-2(3H)-thione (I2) were synthesized and investigated as corrosion inhibitors for carbon steel in 0.5 M HCl solution by means of electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, ATR-FTIR spectroscopy and SEM. The results showed that the investigated mercaptoimidazole derivatives act as mixed type inhibitors and inhibition efficiency follows the I2>I1 order. Adsorption of inhibitors on metal surface was found to obey the Langmuir adsorption isotherm. Thermodynamic parameters revealed that adsorption of the inhibitors has both physisorption and chemisorption adsorption mechanism. Electrochemical test results were supported by quantum chemical parameters obtained from DFT calculations.

• 생명과학회지
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• 제32권5호
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• pp.362-367
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• 2022

대마씨의 외종피를 탈각하여 Tetrahydrocanabinol이 제거된 헴프씨드는 건강식품으로 각광받고 있으며, 헴프씨드 오일은 α-linolenic acid 및 γ-linolenic acid 등의 다가 불포화 지방산 및 지용성 비타민 등이 풍부하여, 인지 기능 및 운동기능 개선, 콜레스테롤 감소, 혈관 염증 완화, 혈전 생성 억제, 신경세포 손상 방지 등의 효능이 알려지면서 수요가 급증하고 있다. 현재 헴프씨드 오일은 여타의 식물성 유지(콩기름, 옥수수유, 올리브유, 카놀라유, 아미씨유)보다 45~140배 이상 고가로 판매되고 있다. 본 연구에서는 FTIR, FTIR-Raman, ATR-FTIR-MIR spectroscopy와 같은 고가의 장비와 전문인력에 의한 분석 없이도 헴프씨드 오일의 진위여부를 판별할 수 있는 간편한 UV-Vis spectrophotometry법을 개발하고자 하였으며, 다양한 오일의 245, 305, 및 415 nm 흡광도를 측정하고, 245/415 nm 및 305/415 nm에서의 흡광도의 비를 계산하여 12.9 및 9.6이 나타나는 경우 헴프씨드 오일임을 확인하였다. 콩기름, 옥수수유, 카놀라유 및 아미씨유의 경우에는 각각 35.4~61.8 및 29.7~50.8을 나타내어 헴프씨드 오일과 쉽게 구분 가능하였다. 상기의 방법은 헴프씨드 오일에 여타의 식물성 유지류를 혼합하는 경우에도 혼합 여부 판별에 이용 가능하였다.