• Textile Coloration and Finishing
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• v.8 no.6
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• pp.9-26
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• 1996

이 연구의 목적은 에틸렌이민 유도체를 갖는 아조계 분산 염료의 나일론 6.6 섬유에의 응용과 최적화된 폴리에스테르 및 나이론 극세사 섬유 염색 조건의 확립이다. 세가지 아지리디닐 모노 아조 염료와 이들 염료의 가수분해 된 형태 그리고 디메틸아닐린계 아조 염료의 폴리에스테르 및 나일론 6.6 극세사 섬유에 대한 염색 및 견뢰도 성질이 조사되었다. 염색 조건 중 pH의 변화에 따른 섬유상의 염착량 변화 조사에서 뚜렷한 경향을 얻을 수 없었으며, 이는 극세사 섬유의 물리적 성질이 두드러지게 착용한 이유라 여겨진다. 염색된 폴리에스테르 극세사 섬유상에서, 아지리디닐 염료는 이들의 가수 분해된 형태 그리고 디메틸아닐린계 아조 염료의 비교하여 개선된 견뢰도 성질을 나타내었다. 아지리디닐 아조 염료의 나일론 극세사 섬유 염색 시 pH 증가에 따라 세탁 및 광견뢰도가 개선되었고, pH8의 염색 조건에서 최적 견뢰도 개선을 나타내었다. 아지리디닐 아조 염료가 이들 염료의 가수분해 된 형태 그리고 디메틸아닐린계 아조 염료와 비교하여 폴리에스테르 및 나일론 섬유상에서 보다 개선된 견뢰도 성질을 나타내었고 이는 섬유와 염료간의 공유 결합으로 기인한 것으로 여겨진다.

• Textile Coloration and Finishing
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• v.8 no.5
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• pp.25-48
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• 1996

이 연구의 목적은 에틸렌이민 유도체를 갖는 아조계 분산 염료의 폴리에스테르 섬유에의 응용과 최적화된 폴리에스테르 염색 조건의 확립이다. 이들 아지리디닐 염료는 구조가 유사하며 말단에 하이드록시기를 갖는 염료(아지리디닐 염료의 가수분해 형태)와 비교하여 최대 흡수 파장의 천색적으로 천이 됨을 알 수 있었다. 세가지 아지리디닐 모노 아조 염료와 이들 염료의 가수분해 된 형태 그리고 디메틸아니린계 아조 염료의 폴리에스테르 섬유에 대한 염색 및 견뢰도 성질이 조사되었다. 아지리디닐 아조 염료는 산성 조건에서보다 염기성 조건하에서 보다 안정하였고, 뛰어난 build-up이 높은 pH조건에서 얻어졌으며, 폴리에스테르 염색 시 130$^{\circ}C$, pH 10의 조건에서 최적화된 색상 강도를 얻었다. 아지리디닐 염료는 이 염료의 가수분해 형태와 디메틸아닐린 염료와 비교하여 개선된 세탁 견뢰도를나타내었고 이는 용매 추출을 이용하여 확인 하였다. 아지리디닐 아조 염료는 역시 광 련뢰도에서도 또한 상용화된 분산 염료에 비교하여 높은 결과를 나타내었다.

• Polymer(Korea)
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• v.36 no.4
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• pp.531-535
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• 2012

Conductive polyaniline (PANI) nanofibers in UV-curable resin were used for a transparent conductive film. The emeraldine-salt PANI (ES-PANI) nanofibers were prepared by chemical oxidation polymerization of aniline, which could be changed into emeraldine-base PANI by dedoping. EB-PANI nanofibers as a precursor for conductive fillers were thereby transformed into re-dpoed PANI (rES-PANI) by dodecylbenzenesulfonic acid in the UV-curable resin solution. rES-PANI nanofibers have high conductivity and long-term stability in the solution without a defect of nanostructure. The resulting conductive resin solution was proved to be highly stable where no precipitation of rES-PANI fillers was observed over a period of 3 months. The transparent film was spin-casted on a poly(methyl methacrylate) sheet of thickness ca. $5{\mu}m$. A surface resistance of $6.5{\times}10^8{\Omega}/sq$ and transmittance at 550 nm of 91.1% were obtained for the film prepared with a concentration of 1.4 wt% rES-PANI nanofibers in the solution. This transformation process of rES-PANI from ES-PANI by dedoping-redoping can be an alternative method for the preparation of an antistatic protection film with controllable surface resistance and optical transparencies with the PANI concentration in UV-curable solution.

• Journal of Food Hygiene and Safety
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• v.30 no.1
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• pp.81-86
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• 2015

The purpose of our paper was to investigate the migration level of 4,4'-MDA(4,4'-methylenedianiline), 2,4-TDA(2,4-toluenediamine), aniline, acrylonitrile and methylmeth acrylate from plastic cookwares into food simulants and to evaluate the safety of each monomers. The test articles for monomers were PA (polyamide) items for 4,4'-MDA, 2,4-TDA and aniline, PU (polyurethane) items for 4,4'-MDA, ABS (acrylonitrile-butadiene- styrene) items for acrylonitrile, and acrylic resin items for methylmethacrylate. All the article samples of 321 intended for contact with foods were purchased in domestic market. 4,4'-MDA, 2,4-TDA and aniline were analyzed by LC-MS/MS (liquid chromatography -tandem mass spectrometer), acrylonitrile by GC-NPD (gas chromatography-nitrogen phos phorus detector) and methyl methacrylate by GC-FID (gas chromatography-flame ionization detector). The migration level of monomers were within the migration limits of Ministry of Food and Drug Safety (MFDS). As a result of safety evaluation, our results showed that the estimated daily intake (EDI, mg/kg bw/day)s were $2.39{\times}10^{-9}$ and $1.20{\times}10^{-9}$ for 4,4'-MDA and 2,4-TDA of PA, $4.32{\times}10^{-9}$ for acrylonitrile of ABS and $2.27{\times}10^{-7}$ for methylmethacrylate of acrylic resin. Reference Dose (RfD, mg/kg bw/day) of acrylonitrile and tolerable daily intake (TDI, mg/kg bw/day) of methacrylate were established respectively as 0.001 by EPA (US Environmental Protection Agency) and as 1.2 by WHO (World Health Organization). When comparing with RfD and TDI, the EDIs of acrylonitrile and methylmethacrylate accounted for $4.32{\times}10^{-4}%$ and $1.89{\times}10^{-5}%$ respectively.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.316-322
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• 2002

This paper presents the temperature-dependent hysteresis identification of an electro-rheological (ER) fluid under various operating temperatures using the Preisach model. As a first step, polymethylaniline (PMA) particles are prepared and mixed with silicone oil to make an ER fluid. A couette type electroviscometer is then employed to obtain the field-dependent shear stress. In order to show the suitability of the Preisach model to predict a physical hysteresis phenomenon of the ER fluid, two significant properties; the minor loop property and the wiping-out property are experimentally examined under three dominant temperature conditions. Subsequently, the Preisach model fur the PMA-based ER fluid is identified using experimental first order descending (FOD) curves. The effectiveness of the identified hysteresis model is verified in the time domain by comparing the predicted field-dependent shear stress with the measured one under the both specified and unspecified temperatures. In addition, the hysteresis model proposed in this work is compared to Bingham model.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.8
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• pp.648-656
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• 2002

This paper presents the identification of temperature-dependent hysteresis of an electro-rheological (ER) fluid under various operating temperatures using the Preisach model. As a first step, polymethylaniline (PMA) particles are prepared and mixed with silicone oil to make an ER fluid. A couette type electroviscometer is then employed to obtain the field-dependent shear stress. In order to show the suitability of the Preisach model to predict a physical hysteresis phenomenon of the ER fluid, two significant properties; the minor loop property and the wiping-out property are experimentally examined under three dominant temperature conditions. Subsequently, the Preisach model for the PMA-based ER fluid is identified using experimental multiple first order descending (FOD) curves. The effectiveness of the identified hysteresis model is verified in the time domain by comparing the predicted field-dependent shear stress with the measured one under the both specified and unspecified temperatures. In addition, the hysteresis model proposed in this work is compared to Bingham model.