• 공업화학
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• 제31권3호
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• pp.267-276
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• 2020

Oxirane계 단량체의 양이온 개환 공중합반응으로 합성되는 ECH (ephichorohydrin) 기반 copolyol (PECH copolyol)류의 특성에 대한 반응온도, 용매의 종류 및 개시제에 대한 영향을 연구하였다. 공단량체로는 butylene oxide와 hexylene oxide 두 종류의 알킬렌 옥사이드를 사용하였으며, 중합 조건은 methylene chloride (MC) 용매에서 개시제로 diethylene glycol (DEG)를 사용한 조건과 toluene을 용매에서 tripropylene glycol (TPG)를 개시제로 사용한 두 조건으로 진행하였다. 개환 공중합반응에서 active monomer (AM) mechanism 유도를 위해 단량체는 실린지 펌프를 사용해 IMA (increased monomer addition) 방법으로 주입하였고 중합온도는 -5 ℃에서 실행하였다. 합성된 ephichorohydrin (ECH) 기반 copolyol인 PECH copolyol은 치환반응으로 ECH unit를 아지드화하여 glycidyl azide계 에너지 함유 copolyol (GAP copolyol)로 전환하였다. 합성된 아지드화 코폴리올은 용매와 개시제의 변화에 대한 영향은 크지 않았으며, 분자량은 아지드화 반응 후 평균 500 증가함으로써 GAP 코폴리올이 설계한 대로 중합되었음을 확인하였다. DSC 분석으로 copolyol류의 조성비 변화에 따른 유리전이 온도(glass transition temperature, T_g)의 변화를 측정하였을 때, 공단량체의 함량이 증가할수록 알킬 사슬의 길이에 의한 영향으로 T_g와 점도가 모두 감소하는 경향을 보였다. 아지드화 반응과정에서 생성되는 CH₃N₃의 생성을 원천적으로 방지할 수 있으며, 대규모 공정이 가능할 것으로 기대된다.

• Journal of Pharmaceutical Investigation
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• 제31권4호
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• pp.217-224
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• 2001

To develop a novel transdermal delivery system of loxoprofen (LP), a potent antiinflammatory and analgesic agent, the effects of various vehicles and penetration enhancers on the skin permeation of LP from solution formulations were investigated. The permeation rate of LP through excised guinea pig skin was measured using a side-by-side permeation system at $32^{\circ}C$. The solubilities of LP in various vehicles were determined by the equilibrium solubility method, and partition coefficients $(P_c)$ were determined. The solubility of LP increased in the rank order of water & isopropyl myristate (IPM) & glyceryl dicaprylate/dicaprate & propylene glycol dicaprylate/caprate & propylene glycol laurate (PGL) & polyethylene glycol 400 & diethylene glycol monoethyl ether (DGME) & ethanol. n-Octanol-water $P_c$ value was 15.5. Among pure vehicles tested, IPM and PGL showed highest fluxes of $89.9{\pm}5.0$ and $45.4{\pm}0.3\;{\mu}g/cm^2/hr$ from saturated solutions, respectively. However, it was not possible to demonstrate any correlation between the solubility of LP and its permeation rate, indicating the change in the barrier property of the skin and/or carrier mechanisms by vehicles tested. The addition of DGME to IPM or PGL markedly increased the solubility of LP, but the permeation rate did not decrease when the concentration of DGME in the cosolvent was increased upto 40%. The addition of linoleic acid (3%) in the cosolvent slightly increased the permeation rate, but others such as lauroyl sarcosine, fatty alcohols and fatty acids tested did not show enhancing effect. In conclusion, the DGME-IPM or DGME-PGL cosolvent system proved to be a good vehicle to enhance the skin permeation of LP.

• 한국결정성장학회지
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• 제12권2호
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• pp.73-79
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• 2002

코발트, 니켈, 구리 그리고 귀금속분말에 적용할 수 있는 polyol법은 균질한 크기와 형상을 갖는 금속분말합성에 매우 효과적인 공정이다 이 때 polyol은 용매, 환원제 그리고 보호제의 역학을 한다 $AgNO_3$글 촉매제로 첨가하여 비균질계 핵생성 반응을 야기할 경우 서브마이크폰 크기(0.5$\mu$m)의 코발트 분말을 한성학 수 있었다. 또한 촉매제인 Ag 핵의 수출 변화시키므로써 코발트 분말의 입도를 제어할 수 있음을 확인하였다.

• 한국정밀공학회지
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• 제31권8호
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• pp.737-742
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• 2014

This paper reports a customized silver ink and its inkjet printing process on a cellulose electro-active paper (EAPap). To synthesize a silver ink, silver nanoparticle is synthesized from silver nitrate, polyvinylpyrrolidone and ethylene glycol, followed by adding a viscosifier, hydroxyethyl-cellulose solution, and a surfactant, diethylene glycol. The silver ink is used in an inkjet printer (Fujifilm Dimatix DMP-2800 series) to print silver electrodes on cellulose EAPap. After printing, the electrodes are heat treated at $200^{\circ}C$. The sintered electrodes show that the thickness of the electrodes linearly increases as the number of printing layers increases. The electrical resistivity of the printed electrodes is $23.5{\mu}{\Omega}-cm$. This customized ink can be used in inkjet printer to print complex electrode patterns on cellulose EAPap to fabricate flexible smart actuators, flexible electronics and sensors.

• 약학회지
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• 제44권3호
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• pp.263-271
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• 2000

In an attempt to develop an injectable form of practically insoluble biphenyl dimethyl dicarboxylate (DDB), the effect of various vehicles, cosolvents and hydrotropic agents was investigated. It was found that polyethylene glycol (PEG) 400 revealed the best solvency toward DDB (17.7 mg/ml at $37^{\circ}C$), and decreasing order of the solubility was as follows: PEG 400>PEG 300>diethylene glycol monoethyl ether (DGME)>PEG-8 glyceryl caprylate/caprate. Among the hydrotropes used, sodium salicylate, sodium benzoate and nicotinamide were effective in increasing the solubility in water. The solubility of DDB in 2 M sodium salicylate, sodium benzoate and nicotinamide solutions was increased 44.3, 23.5 and 44.0 times than that in water, respectively. The addition of sodium salicylate and sodium benzoate to PEG 300-water PEG 400-water and DGME-water cosolvents remarkably increased the solubility of DDB, and significantly retarded precipitate formation when mixed with water Hemolytic properties of DDB injections (2 mg/4~10 ml) in PEG 300-water or DGME-water (60:40 v/v) cosolvents containing sodium benzoate (0.14~0.35 M) were very low. It was concluded from the results that these solutions would be applied to the design of new DDB injections.

• 한국응용과학기술학회지
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• 제26권3호
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• pp.317-327
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• 2009

In this study DMT(Dimethylterephthalate), NDC(Dimethyl-2, 6-Naphthalene Dicarboxylate) were used to synthesize polyester polyol which shows enhanced storage stability, improved flame retardancy, and good compressive strength. If DMT and NDC react respectively with DEG(Diethylene Glycol) which is kind of linear diol, the obtained polyester polyols tend to crystallize easily after the reaction. In case of DMT, PA(Phthalic Anhydride) which has asymmetric structure was introduced to retard the crystallization. In case of NDC, DPG(Dipropylene Glycol) which has an methyl side chain was introduced to prevent the crystallization. It was found that to introduce DPG was much more effective method to prevent the crystallization than PA. NDC and DMT were reacted together with DPG for various compositions of NDC:DMT(8:2, 6:4, 4:6 mol ratio). The obtained NDC-DMT-DPG based polyester polyol showed improved flame retardancy, and good compressive strength with increasing the content of NDC.

• Biomolecules & Therapeutics
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• 제9권4호
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• pp.298-306
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• 2001

To develop a novel transdermal delivery system of loxoprofen (LP), a potent antiinflammatory and analgesic agent, the effects of vehicle composition and drug loading dose on the skin permeation property were investigated. And in vivo skin absorption property studied by analysing the $C_{max}$ and AUC was investigated after applying the developed plaster systems on rabbit back skin. Addition of isopropyl myristate (IPM) and IPM-diethylene glycol monoethyl ether (DGME) cosolvent in the plaster showed higher permeation rates than those from propylene glycol laurate-DGME cosolvent systems. As the concentration of LP in the plaster increased from 0.56 mg/$\textrm{cm}^2$ to 1.19 mg/$\textrm{cm}^2$, the drug release and skin permeation rates increased linearly. At loading dose of 1.19 mg/$\textrm{cm}^2$, the flux reached 35.6 $\mu$g/$\textrm{cm}^2$/hr. New LP plasters showed a good adhesive property onto skin, and showed no crystal formation. The AU $C_{0-24hr}$ and $C_{max}$ after dermal application of LP plaster (60 mg/70 $\textrm{cm}^2$) were found to be 6951$\pm$230 ng.hr/ml and 400$\pm$44 ng/ml, respectively. And the plasma concentration maintained above 300 ng/ml up to 24 hr period. In the carrageenan-induced rat paw edema test, LP plaster showed similar inhibition rate with marketed ketoprofen (Ketoto $p^{R}$) plaster.aster.r.

• Macromolecular Research
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• 제16권5호
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• pp.424-428
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• 2008

We prepared an ionic gel polymer electrolyte for dye-sensitized solar cells (DSSCs) without leakage problem. Triiodide compound (BTDI) was synthesized by the reaction of benzene tricarbonyl trichloride with diethylene glycol monotosylate and subsequent substitution of tosylate by iodide using NaI. Bisimidazole was prepared by the reaction of imidazole with the triethylene glycol ditosylate under strongly basic condition provided by NaH. BTDI and bisimidazole dissolved in an ionic liquid were injected into the cells and permeated into the $TiO_2$ nanopores. In situ crosslinking was then carried out by heating to form a network structure of poly(imidazolium iodide), thereby converting the ionic liquid electrolytes to a gel or a quasi-solid state. A monomer (BTDI and bisimidazole) concentration in the electrolytes of as low as 30 wt% was sufficient to form a stable gel type electrolyte. The DSSCs based on the gel polymer electrolytes showed a power conversion efficiency of as high as 1.15% with a short circuit current density of $5.69\;mAcm^{-2}$, an open circuit voltage of 0.525 V, and a fill factor of 0.43.

• 한국염색가공학회지
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• 제34권1호
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• pp.10-19
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• 2022

Humectants are chemical compounds which added to water based pigment inks for DTP (Digital Textile Printing) to prevent evaporation of water. The humectants usually have diol or triol type chemical structures and their -OH groups have possibility to react with functional groups of the binder polymers, such as ester, carboxylic acid, and urethane groups, acting as a crosslinking agent. The crosslinking reactions between polymer binders and humectants in inks can affect touch of the printed fabrics. In this regard, this study aims to investigate effect of chemical structures and added amounts of humectants in pigment ink on touch of dyed fabrics by using 1,6-hexanediol, ethylene glycol, diethylene glycol, and 1,4-buthanediol with various amounts added to the mixture of a black pigment and a polyurethane type binder. Then, color, rubbing strength, touch of the fabrics dyed with the prepared pigment inks were evaluated.

• 대한기계학회논문집B
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• 제27권12호
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• pp.1691-1698
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• 2003

In this paper, the combination effects of oxygen component in fuel and exhaust gas recirculation on the exhaust emissions have been investigated for a direct injection diesel engine. It is a kind of effective oxygenated fuel of diether group that the smoke emission of DGM(diethylene glycol dimethyl ether) blended fuel is reduced remarkably compared with commercial diesel fuel, that is, it can supply oxygen component sufficiently at higher loads and speeds in diesel engine. But, NOx emission of oxygenated fuel was increased compared with commercial diesel fuel. Also, the effects of exhaust gas recirculation(EGR) on the characteristics of NOx emission has been investigated. It was found that simultaneous reduction of smoke and NOx was achieved with oxygenated fuel(DGM 5vol-%) and cooled EGR method(10∼15%).