• 한국염색가공학회지
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• 제29권2호
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• pp.55-61
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• 2017

A non-fluorinated polystearyl methacrylate water repellent was synthesized by emulsion polymerization. The number and weight averaged molecular weights were obtained at around 137,277 and 237,754g/mole. The melting point was observed at $32^{\circ}C$. The contact angle of water droplet on fabrics treated with the water repellent was $140{\sim}145^{\circ}$ for cotton and polyester, and $125{\sim}130^{\circ}$ for wool and nylon. Since the critical surface tension was estimated at 20.7mN/m, even though relatively not so strong as fluorinated water repellent, it is considered to be used as a good water repellent practically.

• BMB Reports
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• 제37권5호
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• pp.586-596
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• 2004

The folding of ervatamin C was investigated in the presence of various fluorinated and non-fluorinated organic solvents. The differences in the unfolding of the protein in the presence of various organic solvents and the stabilities of O-states were interpreted. At pH 2.0, non-fluorinated alkyl alcohols induced a switch from the native $\alpha$-helix to a $\beta$-sheet, contrary to the $\beta$-sheet to $\alpha$-helix conversion observed for many proteins. The magnitude of ellipticity at 215 nm, used as a measure of $\beta$-content, was found to be dependent on the concentration of the alcohol. Under similar conditions of pH, fluorinated alcohol enhanced the intrinsic a-helicity of the protein molecule, whereas the addition of acetonitrile reduced the helical content. Ervatamin C exhibited high stability towards GuHCl induced unfolding in different O-states. Whereas the thermal unfolding of O-states was non-cooperative, contrary to the cooperativity seen in the absence of the organic solvents under similar conditions. Moreover, the differential scanning calorimetry endotherms of the protein acquired at pH 2.0 were deconvoluted into two distinct peaks, suggesting two cooperative transitions. With increase in pH, the shape of the thermogram changed markedly to exhibit a major and a minor transition. The appearance of two distinct peaks in the DSC together with the non-cooperative thermal transition of the protein in O-states indicates that the molecular structure of ervatamin C consists of two domains with different stabilities.

• 대한화장품학회지
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• 제23권3호
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• pp.75-81
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• 1997

It has been used that fluorinated compounds could be applied to cosmetic products. It is that fluorinated conpounds are hydrophobicity and lipophobicity. These fluorinated compounds are reported to form a highly protective and effective film against most aggressive chemical and physical agents. PerfluropolymethyoisopropylEther has homophobicity and are colorless, odorless, tasteless and non-greasy. In this we made a success to formulate the new type of hand care cream using PFPE. PFPE are suitable thickness and chemical inertness to skin. The reason that we select PFPE for this investigation. We developed the new type hand care cream by adsorption and dispersion of PFPE. There are very stable dispersion and highly moisture diffusion control. And these characteristics were verified by actual consumer test.

• 대한화장품학회지
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• 제23권3호
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• pp.152-160
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• 1997

It has been used that fluorinated compounds could be applied to Make-up products. It is that fluorinated compounds are hydrophobicity, lipophobicity and homophobicity. These fluorinated compounds are reported to form a highly protective and effective film against most aggressive chemical and physical agents. In this study we maed a success to formulate the new type of lipstic using perfluoropolymethylisopropylether with low molecular weight which is long wearing and comfortable to use. This PPIE was adsorbed more than 90% in this experiment and formed the well-balanced gel networks even if the selected PPIE is 100% volatile at room temperature. On the basis of the adsorption of PPIE, we developed the new type lipstick, which was highly-lip feeling and had long wearing and non coloration. And these characteristics were verified by actual consumer test.

• Bulletin of the Korean Chemical Society
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• 제12권4호
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• pp.449-453
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• 1991

The degree of electrophilic interference on the solvolytic reactions of model substrates has been studied in fluorinated alcohol solvent mixtures. With variation of solvent composition of 1,1,1,3,3,3-hexafluoro-2-propanol(HFP) and 2-propanol (PrOH) mixtures, the magnitude of electrophilic solvent assistance was changed inversely with the degree of nucleophilic solvent assistance. The contribution of electrophilic interference for 2-adamantyl tosylate showed higher than tert-butyl chloride in HFP-PrOH mixtures. Through a correlation of nucleophilic solvent assistance and electrophilic solvent assistance based on the method of double differences, HFP-PrOH mixture showed a big discrepancy from non-fluorinated alcohol systems.

• Korean Chemical Engineering Research
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• 제51권5호
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• pp.556-560
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• 2013

최근에 저가의 고분자전해질 연료전지(Proton Exchange Membrane Fuel Cells, PEMFC)용 비불소계 전해질 막 연구개발이 활발히 진행되고 있다. 본 연구에서는 PEMFC 운전 조건에서 Poly(arylene ether sulfone)(PAES) 막과 불소계막의 특성을 비교하였다. I-V 분극곡선, 수소투과도, 전기화학적 표면적, 막저항 및 부하 전달 저항 등을 측정 분석했다. PAES 막은 상대습도 100%에서는 불소계 막과 비슷한 성능을 보였으나 낮은 상대습도에서 이온전도도가 낮아 성능감소가 컸다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.933-935
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• 2002

In this paper, new non-chiral molecules with semi-fluorinated alkyl chains were synthesized varying the structure of central bent core unit. Their mesomorphic properties were investigated by DSC and polarized microscopy. The compound with 1,3-dihydroxy phenylene unit could form an enantiomeric smectic phase, but the remaining compounds with bent-core mesogenic unit were not liquid crystalline. In this presentation, their x-ray measurement and electro-optical property will be also described.

• 공업화학
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• 제9권5호
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• pp.619-623
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• 1998

불화된 금속 산화물 촉매상에서 이염화메탄을 불화하여 이불화메탄을 합성하는 연구를 하였다. 실험 변수는 반응온도, HF/DCM (dichloromethane) 몰비, 접촉시간 그리고 촉매의 형태이었다. 촉매의 성능은 불화된 알루미나 보다는 크롬이 담지된 불화된 알루미나가 우수하였으며 크롬을 담지한 촉매에서 전처리 하지 않은 경우가 수소와 공기 분위기로 소성처리한 경우보다 더욱 우수하였다. 최적 반응 조건은 반응온도 $340^{\circ}C$, HF/DCM 몰비 5이상 그리고 접촉시간 20 초 이상이었다. 이들 조건에서 얻은 이불화메탄의 최대 수율은 80% 이상이었다. 특히 반응시간이 8시간까지 촉매의 활성 감소나 이불화메탄의 선택성의 감소가 나타나지 않았다.

• Bulletin of the Korean Chemical Society
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• 제27권9호
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• pp.1364-1370
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• 2006

New liquid-crystalline biphenyl carboxylates with an achiral swallow-tail derived from 1,3-dialkoxy-2-propanol $[(ROCH_2)_2CHOH$] where R is methyl, ethyl, propyl, butyl, $CH_2CF_3$, and $CH_2CF_2CF_3$ were prepared. These achiral liquid crystals having 1,3-dialkoxy-2-propyl moieties exhibit diverse phase sequences [I-SmA-(SmC)-(SmCalt)-Cr] depending on the substituent R group of the swallow-tail. The compounds carrying a fluorinated swallow-tail exhibit antiferroelectric-like smectic C phases, and their temperature ranges are broader than the corresponding non-fluorinated swallow-tailed ones.

• Bulletin of the Korean Chemical Society
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• 제26권3호
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• pp.393-398
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• 2005

The stability constants for the diaza-18-crown-6 ethers 2-6 and alkali metal cations ($Na^+,\;K^+,\;Rb^+\;and\;Cs^+$) were determined using potentiometry in 95% methanol. For each metal ion the stability constants of the partiallyfluorinated ligands 3-6 were larger than that of the non-fluorinated ligand 2, which might reflect an interaction between fluorine atoms and alkali metal cations. The stability constant of the ligand 4 was larger than that of the ligand 5 for each metal cation tested. This finding was also supported by the results of cation-induced chemical shifts in $^1H-,\;^{19}F$-NMR and extraction experiment. The potentiometry and NMR results as well as the X-ray crystal structures revealed that the position and number of fluorine atoms in the benzyl side arms was crucial for the enhanced interaction between a ligand and an alkali metal.