• Title/Summary/Keyword: sulfonic acid

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Perfluorinated Sulfonic Acid Ionomer-PTFE Pore-filling Membranes for Polymer Electrolyte Membrane Fuel Cells (고분자전해질연료전지용 과불소계 술폰화 이오노머-PTFE 강화막)

  • Kang, Seong Eun;Lee, Chang Hyun
    • Membrane Journal
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    • v.25 no.2
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    • pp.171-179
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    • 2015
  • Perfluorinated sulfonic acid ionomers (PFSAs) have been widely as solid electrolyte materials for polymer electrolyte membrane fuel cells, since they exhibit excellent chemical durability under their harsh application conditions as well as good proton conductivity. Even PFSA materials, however, suffer from physical failures associated with repeated membrane swelling and deswelling, resulting in fairly reduced electrochemical lifetime. In this study, pore-filling membranes are prepared by impregnating a Nafion ionomer into the pore of a porous PTFE support film and their fundamental characteristics are evaluated. The developed pore-filling membranes exhibit extremely high proton conductivity of about $0.5S\;cm^{-1}@90^{\circ}C$ in liquid water.

Clinical improvement of amino propane sulfonic acid and it's quantitative measurement with a new opticoprofilometry (Amino propane sulfonic acid의 임상적 개선효과 및 새로운 opticoprofilometry 방법에 의한 정량분석)

  • 선보경;이해광
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.21 no.1
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    • pp.1-18
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    • 1995
  • We had tested the effect of amino propane sulfonic acid(APSA) on the human skin with non-invasive technique. It was tested with four parameters that were hydration, elasticity, color and skin wrinkles. In vitro culture systems, APSA stimulated the proliferation of fibroblasts bolt it didn't stimulate that of keratinocyte. Also we obtained the similar effects in the raft culture method. So we concluded that APSA affected the dermal region than the epidermal region. In clinical tests, APSA changed the skin color, pbiomechanical properties(especially elasticity) and reduced skin wrinkles of the volunteers. And we could get the better results of skin wrinkle improvement by use of Skin Visiometer than Silflo Image analysis systems.

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Capture of Metal Ions by Cross-linked Sulfonic Acid Type Ion Exchange Membranes (가교제를 도입시킨 술폰산형 이온교환막의 금속이온 포집)

  • Kim, Min;Kim, Ye-Jin;Park, Sang-Jin
    • Membrane Journal
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    • v.19 no.4
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    • pp.333-340
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    • 2009
  • This paper is designed with the purpose of improving the efficiency of the sulfonic acid ion exchange membranes by radiation induced graft polymerization. It has been shown that the porous hollow fiber membranes could cause permeability blocking between pores and ion exchanged graft chains. Addition of crosslinker such as N-ethylene glycol dimethacrylate will permit to increase the permeation flux. In this research, the ethylene glycol dimethacrylate (EDMA) and diethylene glycol dimethacrylate (DDMA) with different length are used as crosslinkers. The ion exchanged cross-linked membrane (EDMA, DDMA) containing sulfonic acid group by radiation induced grafted polymerization are sn died for adsorb metal ions (Pb). It has been shown that adsorbed metal ions ($Pb^{2+}$) for the EDMA and DDMA membranes with the density of sulfonic acid groups, 1.40 mmol/g and 2.14 mmol/g, respectively are 13.82 mg/g, 17.37 mg/g, accordingly.

Hydrolytic Stability of Sulfonic Acid-Containing Polyimides for Fuel Cell Membranes

  • Kim Hyoung-Juhn;Litt Morton H.;Shin Eun-Mi;Nam Sang Yong
    • Macromolecular Research
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    • v.12 no.6
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    • pp.545-552
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    • 2004
  • The long-term stability of sulfonic acid-containing polyimides has been investigated. The hydrolytic degradation of homopolyimide and the block copolyimide comprising $27\;mol\%$ of 2,2'-bis(trifluoromethyl)benzidine and $9\;mol\%$ of m-phenylenediamine (BTFMB27mPl0[7/(3+1)]), was quantified through viscosity measurements and FT-IR spectroscopic analyses. The viscosity decrease with respect to time and the degradation rate were similar. The degrees of degradation with respect to time under ambient conditions and at elevated temperature in water were monitored by FT-IR spectroscopy. A new absorption peak was observed at $1786\;cm^{-1},$ which we corresponds to the presence of anhydride end groups formed by hydrolytic scission of the imide rings.

Application of X-ray photoelectron spectroscopy (XPS) in ionic liquids

  • Park, Ju-Yeon;Seo, Cho-Hyeon;Seo, Seong-Yong;Gang, Yong-Cheol
    • Proceedings of the Korean Vacuum Society Conference
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    • 2015.08a
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    • pp.117-117
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    • 2015
  • Availability of X-ray photoelectron spectroscopy (XPS) for the identification of ionic liquids (ILs) was tested. Commercially available ionic liquids (1-butyl-3-methyl imidazolium tetrafluoroborate ([BMIM] $BF_4$), (1-butyl-3-methyl imidazolium trifluoromethanesulfonate ([BMIM] OTf), (1-butyl-3-methyl imidazolium hexafluorophosphate ([BMIM] $PF_6$), 1-hexyl-3-imidazolium hexafluorophosphate ([HMIM] $PF_6$), and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM] $Tf_2N$) were qualitatively and semi-quantitatively analyzed with XPS. In order to confirm whether the results of XPS were correct, conventional method such as a nuclear magnetic resonance (NMR) was performed. After the XPS results were convinced by NMR, we synthesized ILs (1-(4-sulfonic acid) butyl-3-butylimidazolium trifluoromethanesulfonate ([SBBIM] OTf), 1-(4-sulfonic acid) propyl-3-methylimidazolium trifluoromethanesulfonate ([SPMIM] OTf), and 1-(4-sulfonic acid) propyl-3-butylimidazolium trifluoromethanesulfonate ([SPBIM] OTf) and analyzed it with XPS and NMR as well. It was successful the usage of XPS to analyze ILs without any purification processes.

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The Effect of Reaction Conditions on the Conversion of Synthesis of 1-Amino-4-(3'-Acetaminoanilino) Anthraquinone-2-Sulfonic Acid (1-Amino-4-(3'-Acetaminoanilino) Anthraquinone-2-Sulfonic Acid 합성의 전화율에 미치는 반응조건의 영향)

  • 천재기;구수진
    • Journal of the Korean Graphic Arts Communication Society
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    • v.16 no.3
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    • pp.133-146
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    • 1998
  • The conversion of 1-Amino-4-(3'-Acetaminoanilino) Anthraquinone-2-Sulfonic Acid prepared by the Ullmann condensation have been investigated as a function of the reaction conditions such as catalysts, initial concentration of reactants, reaction temperature, pH, condensation agents and neutralizing agents. The experimental results showed that the Cu(I)-type catalysts had higher activity than the Cu(II)-type catalysts in this study. The conversion increased with increasing initial concentration of reactants but decreased at above critical concentration owing to agglomeration of reactants. It was also observed that the maximum conversion obtained at 7$0^{\circ}C$ and pH=7~8.

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Studies on the Synthesis of the Isomeric 1-naphtholsulfonic Acids and Analysis of their Mixtures (1-나프톨 술폰산 이성체의 합성 및 혼합물의 분석에 관한 연구)

  • Sohn, Joo-Hwan;Kim, Kwang-Jea;Lee, Seung-Yeell
    • Journal of the Korean Applied Science and Technology
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    • v.6 no.2
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    • pp.21-28
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    • 1989
  • 1-naphthol-2-sulfonic acid and 1-naphthol-4-sulfonic acid were synthesized under the dissolution of 1-naphthol in 2-nitrotoluene with stirring 98.08-90% sulfuric acid at $5-95^{\circ}C$ for 1-5 hours. As the reaction temperatures and the reaction time were raised, the yield of 2-sulfonate was decreased, while that of 4-sulfonate was increased. But we could not observe the tendency to the various reaction concentrations of sulfuric acids. The mixtures of two isomeric 1-naphtholulfonic acids in excess concentrated sulfuric acids was quantitatively determinded by using multicomponent spectrophotomeric analysis method on the basis of the ultraviolet absorption peak of the sulfonic acids. The standard deviation in this method was ${\pm}\;2.6$, and the above method seem to be rapid and accurate.

Chemoselective Alkylation of Aromatics with Benzyl Alcohol over Mesoporous ZSM-5

  • Jin, Hailian;Ansari, Mohd Bismillah;Jeong, Eun-Young;Park, Sang-Eon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.200-200
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    • 2011
  • Hierarchical mesoporous ZSM-5 with enhanced mesoporosity was synthesized by microwave through the rapid assembly via ionic interaction between sulfonic acid functionalized ZSM-5 nano particles and cationic surfactant. The catalytic performance of enhanced accessibility due to mesoporosity and acidity were investigated in the alkylation of mesitylene with benzyl alcohol as alkylating agent. The effect of mole ratio of aromatic with benzyl alcohol, reaction time and alkylation agent were also studied. The enhanced mesoporosity and acidity of sulfonic acid functionalized mesoporous ZSM-5 induced activity enhancement compared with non-functionalized mesoporous ZSM-5, sulfonic functionalized mesoporous ZSM-5 synthesized by hydrothermal method and conventional microporous ZSM-5. The sulfonic acid functionalized mesoporous ZSM-5 showed much higher chemoselectivity of benzylated mesitylene than others, whereas the others mainly show dibenzyl ether as product. This significant difference in catalytic selectivity was resulted from the existence of mesopores, which definitely allowed the benzylation in mesopores.

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A Study of Selective Absorption of Metal Ions by Chelating Agent-Loaded Anion Exchange Resins (킬레이트 시약으로 처리한 음이온 교환수지에 의한 금속이온의 선택적 흡착에 관한 연구)

  • Lee Dai Woon;Lee, Won;Yu Euy Kyung
    • Journal of the Korean Chemical Society
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    • v.23 no.3
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    • pp.141-151
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    • 1979
  • The selective absorption of metal ions by chelating agent-loaded resins was studied in aqueous media. The resins were prepared by loading the conventional anion exchange resin, Dowex 1-X8 (50 to 100 mesh) with chelating agents containing sulfonic group, such as 8-hydroxy-quinoline-5-sulfonic acid (HQS) and 7-nitroso-8-hydroxyquinoline-5-sulfonic acid (NHQS). The stability of the resin was markedly influenced by the following factors; (1) the affinity and concentration of anions in the external solution, (2) the pH of the media. The optimum conditions for the absorption of metal ions were determined with respect to the pH, shaking time, and the effect of anion concentration in the medium. Under the optimum condition the order of the absorption of metal ions such as Fe(Ⅲ), Cu(Ⅱ), Pb(Ⅱ), and Zn(Ⅱ) was in accord with that of the stability constants of the chelates. The total capacities of the resins were found in the range of 0.6∼1.6 mmole metal per gram.

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Preparation and Characterization of Acid Amplifiers containing electron withdrawing group (전자끄는기를 갖는 산 증식제의 합성 및 특성 연구)

  • Lee, Eun-Ju;Jeong, Yeon-Tae
    • Journal of the Korean Graphic Arts Communication Society
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    • v.21 no.1
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    • pp.21-34
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    • 2003
  • Acid amplifiers derived from a certain class of sulfonates suffer from autocatalytic decomposition in the presence of a strong acid to give corresponding sulfonic acid, which catalyze the composition of the parent sulfonates, leading to the liberation of more of the same sulfonic acids in an exponential manner. In this research we synthesized and evaluated 4-hydroxy-4'-(2-trifluoromethyl)benzenesulfonyloxy isopropylidene dicyclohexane (1), 4,4'-di-(2-trifluoromethyl)benzenesulfonyloxy isopropylidene dicyclohexane (2), 4-hydroxy-4'-(3-trifluoromethyl)benzenesulfonyloxy isopropylidene dicyclohexane (3) and 4,4-di-(3-trifluoromethyl)benzenesulfonyloxy isopropylidene dicyclohexane (4) as novel acid amplifiers with electron withdrawing group. These acid amplifiers (1-4) showed reasonable thermal stability for resist processing temeprature and exhibited higher photosensitivity compared to poly(tert-butyl methacrylate) film without acid amplifiers. Application of acid amplifiers to photofunctional materials, including photoresists, are described as a consequence of the combination of the acid amplifiers with photoacid generator.

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