• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.224-224
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• 2015

Gel have enormous applicable region due to inherently high stretchability and bio-compatibility. Here, we fabricated highly stretchable electronic conductive organogels which have long-term stability in environment. By introducing a dialysis step which can incorporate conducting polymer, PEDOT, on the procedure of gel synthesis, residual ions inside the gel were removed. In addition, we replaced the water with organic solvent, EG, inside the gels which is high stability in air. Unlike conventional hydrogels, there are no ionic conduction occurred and electrochemically driven current was prevented during electrical voltage was applied. The fabricated organogels are hardly dried during air exposure, and only electrically conductive without any electrochemical reaction at even high voltage. In order to utilize as stretchable conductor, we demonstrated a LED array circuit using the conductive organogels as electrical interconnects. It was successfully operative even stretched up to 300% strain.

• Bulletin of the Korean Chemical Society
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• 제32권4호
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• pp.1258-1262
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• 2011

A new organogelator, L-Alanine dihydrazide derivative can self-assemble in various organic solvents and turned them into thermally reversible physical supramolecular organogels at extremely low concentrations (< 2 wt %). The gel-sol phase transition temperatures ($T_{GS}$) were determined as a function of gelator concentration and the corresponding enthalpies (${\Delta}H_g$) were extracted. Scanning electron microscopy (SEM) measurements revealed that the interspaces of fiber-like network structures were diminished with the increasing of the LMOG concentration. FT-IR spectroscopy studies revealed that hydrogen-bonding and hydrophobic interaction were the driving forces for the formation of the gels. Based on the data of XRD and molecular modeling, the possible packing modes for the formation of organogelator aggregates were proposed.

• Journal of Pharmaceutical Investigation
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• 제21권1호
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• pp.1-10
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• 1991

Hydrogels containing ketoprofen were prepared by adding NaOH or $Ca(OH)_2$ solution to Eudragit L, S and Eudispert hv at various concentration. And xerogels were prepared by drying hydrogels. On the other hand, organogels containing ketoprofen were prepared by mixing Eudragit L or S and propylene glycol. Effects of polymer content and base on drug release were investigated using KP V dissolution method. The release rate of ketoprofen from Eudragit L & S hydrogel decreased with increasing in polymer content. And the drug release rate from cal. hydroxide based gels were more decreased than that from sod. hydroxide based gels. At pH 7.2 dissolution medium, e release of ketoprofen from Edispert hv hydrogel followed apparent zero order kinetics. The release of ketoprofen from xerogel involved in simultaneous absorption of water and desorption of ketoprofen via a pH-dependant swelling controlled mechanism. The release of ketoprofen from Eudragit S organogels followed apparent zero order kinetics, providing strong evidence for a surface erosion mechanism.

• 공업화학
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• 제29권2호
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• pp.244-247
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• 2018

쌍성이온 인지질의 한 종류인 lecithin은 decane과 같은 유기용매상에서 구 모양의 역마이셀을 만든다. 이러한 lecithin을 포함하고 있는 유기졸에 염화칼슘과 같은 다원자가의 이온을 첨가하면 유기젤이 형성된다. 이러한 유기젤은 연료의 젤화, 음식 준비, 약물전달 등에 다양하게 활용될 수 있다. 본 연구에서는 이러한 젤의 온도 영향을 유변학적 관점에서 조사하였다. 유기젤의 유변학 연구를 통하여 유기젤의 녹는점(${\sim}95^{\circ}C$)과 온도가 증가하면서 젤의 고체와 같은 성질이 줄어듦을 확인하였다. 온도가 증가함에 따라서 유기젤의 고체와 같은 성질이 줄어드는 이유는 lecithin과 염화칼슘 사이의 정전기적 상호작용이 약해지기 때문으로 판단된다.

• 접착 및 계면
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• 제24권4호
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• pp.131-135
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• 2023

레시틴은 양친매성 분자로 유기용매상에서 구형의 역 마이셀로 자가조립된다. 이러한 레시틴 용액에 담즙염, 물 등과 같은 첨가제가 들어갈 경우 레시틴의 분자 형태의 구조 변화를 유도하여 역 실린더형 마이셀로의 변환을 이끈다. 이번 연구에서는, 데케인 상에서 레시틴/담즙염 혼합물에 물을 첨가한 후, 유동계를 활용하여 혼합물의 유변학적 변화를 관찰한다. 이렇게 제조된 혼합물들은 점도가 높고 점탄성의 특징을 나타내어 약물전달, 식품젤 등의 다양한 분야에 활용이 가능할 것으로 기대된다.