• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.165-166
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• 2003

완전히 가수분해 된 폴리비닐알콜(PVA)은 에멜전 안정화와 계면활성이 약하다. $^{1)}$ 하지만 hydrophobically modified PVA는 높은 계면활성을 가지고 있을뿐더러 수용액에서 micelle을 형성할 수 있고 게다가 그의 수용액은 높은 viscosity, shear thinning, thixotropic, less salt sensitive 성질을 가지고 있어 enhanced oil recovery operations, drag reduction, flocculation, super absorbency, latex paints, hydraulic fluids, surface coatings등에 사용될 수 있다. $^{2.3)}$ (중략)

• Journal of the Korean Applied Science and Technology
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• v.17 no.2
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• pp.105-112
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• 2000

Surface tension as a function of concentration and temperature was measured for aquous solution of sodium N-acyl sarcosinate, $RCON(CH_{3})CH_{2}$ COONa, From the intersection points in the (${\gamma}-logC$) curves, the critical micelle concentration (cmc) was determined at 20, 30, 40, and $50^{\circ}C$. Structural effects on the cmc maximum and the minimum area per molecule at the aquous solution/air interface were discussed. The free energy, enthalpy, and entropy of micellization and adsorption of surfactant solution also were investigated. Numberous investigators have dealt with sodium N-acyl sarcosinates and their applications as wettings, flooding and reducing agents and as corrosion inhibitors.

• Analytical Science and Technology
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• v.11 no.3
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• pp.151-155
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• 1998

Electrochemical behaviours on 1.0 mM methylviologen ($MV^{2+}$) in 100 mM NaCl+27 mM $MgCl_2$ solution, without and with sodium dodecyl sulfate (SDS), were studied. The intersection of two lines on ${\Delta}E_p$ (the difference between the anodic, $E_{pa}$, and the cathodic, $E_{pc}$, peak potentials) of the first and second redox waves vs. -log[SDS] plot was determined as a critical micelle concentration (CMC). When $Mg^{2+}$ was added, the effective access of $MV{\cdot}^+$ to the glassy carbon electrode surface became possible and the formation of micelles was retarded.

• Journal of the Korean Chemical Society
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• v.39 no.12
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• pp.896-901
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• 1995

The critical micelle concentrations(CMC$^*$) of the mixed surfactant systems of Sodium dodecyl sulfate(SDS) with Tetraethylene glycol monododecyl ether(TGME) in the aqueous solutions of NaCl at $25^{\circ}C$ were determined as a function of the overall mole fraction of $SDS(\alpha1)$ by the use of surface tension method. Various thermodynamic parameters for the micellization of SDS/TGME mixed surfactant systems were calculated and analyzed by means of the equations derived from the nonideal mixed micelle model, based on the pseudo-phase separation model.

• Journal of Microbiology and Biotechnology
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• v.17 no.2
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• pp.313-319
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• 2007

The nutritional medium requirement for biosurfactant production by Bacillus licheniformis K51 was optimized. The important medium components, identified by the initial screening method of Plackett-Burman, were $H_3PO_4,\;CaCl_2,H_3BO_3$, and Na-EDTA. Box-Behnken response surface methodology was applied to further optimize biosurfactant production. The optimal concentrations for higher production of biosurfactants were (g/l): glucose, $1.1;NaNO_3,\;4.4;MgSO_4{\cdot}7H_2O,\;0.8;KCl,\;0.4;CaCl_2,\;0.27;H_3PO_4,\;1.0ml/l;\;and\;trace elements\;(mg/l):H_3BO_3,\;0.25;CuSO_4,\;0.6;MnSO_4,\;2.2;Na_{2}MoO_4,\;0.5;ZnSO_4,\;6.0;FeSO_4,\;8.0;CoCL_2,\;1.0;$ and Na-EDTA, 30.0. Using this statistical optimization method, the relative biosurfactant yield as critical micelle dilution (CMD) was increased from $10{\times}\;to\;105{\times}$, which is ten times higher than the non-optimized rich medium.

• Bulletin of the Korean Chemical Society
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• v.25 no.7
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• pp.1031-1035
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• 2004

The adsorption kinetics of ${\beta}$-casein on a hydrophobic surface has been studied by means of the quartz crystal microbalance (QCM). The self assembled monolayer of 1-octadecanethiol on a gold coated quartz crystal was used as a hydrophobic surface for adsorption. The adsorption kinetics was monitored in different solution conditions. Formation of monolayer is observed in most cases. At high concentration of protein, micelle formation which is interrupted by high ionic strength of solution is observed. Casein binding cations such as $Ca^{2+},\;Ba^{2+}\;and\;Al^{3+}$ increase the hydrophobicity of the protein and the multiple layer adsorption occurs. The strong and weak points of the QCM method in the study of protein adsorption are discussed.

• Korean Journal of Pharmacognosy
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• v.15 no.3
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• pp.134-138
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• 1984

In this study the solubility of cholesterol was examined with ginseng saponin and chemical saponin used in the preparation of reaction mixture of 0.15M NaCl solution. It was shown that the solubility of cholesterol varied in the concentration of ginseng saponins and in the temperature and that the osmotic pressure and the surface tension was amenable to changes in the concentration of ginseng saponins and the incubation period of the reaction mixture. From the results, it was revealed that the solubility of cholesterol was dependent upon the incubated times and the concentration of ginseng saponins in 0.15mM NaCl solution and that ginseng saponins have the cholesterol solubilizing effect as evidenced in the physicochemical properties of mixed micelle formation and surface-activity.

• Journal of Magnetics
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• v.13 no.2
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• pp.53-56
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• 2008

This study proposes a simple nano-patterning process for the fabrication of magnetic nanodot arrays on a large area substrate. Ni nanodots were fabricated on a large area (4 inches in diameter) Si substrate using the soft lithographic technique using self-assembled surface micelles of Polystyrene-block-Poly(methyl methacrylate) (PS-b-PMMA) diblock copolymer formed at the air/water interface as a mask. The hexagonal array of micelles was successfully transferred to a Ni thin film on a Si substrate using the Langmuir-Blodgett technique. After ion-mill dry etching, a magnetic Ni nanodot array with a regular hexagon array structure was obtained. The Ni nanodot array showed in-plane easy axis magnetization and typical soft magnetic properties.

• Journal of the Korean Applied Science and Technology
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• v.9 no.1
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• pp.1-6
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• 1992

New five N-acyl-N-methyl taurate and their sodium salts were synthesized by acylating sodium N-methyl taurate in water in the presense of inorganic alkali as a catalyst. Wherein acyl group is a straight-chain radical of 10 to 18 carbon atoms. These compounds were identified by infrared spectroscopy. Surface activities of these sodium N-acyl-N-methyl taurate including surface tension, Ross-Miles foaming powers, foam stabilities, emulsifying powers and detergency were measured respectively. Also critical micelle concentration(cmc) were evaluated. Consequently these anionic surfactants with long chain acyl amine showed good emulsifying power of O/W type and had a good detergence.

• Bulletin of the Korean Chemical Society
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• v.11 no.1
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• pp.41-44
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• 1990

The rates of electropolymerization of pyrrole from aqueous solutions containing p-toluenesulfonic acid were studied as functions of the concentration of the surfactant anions and of temperature for the polymerization on the electrode surface immersed in the solution and also for the polymerization along the solution surface. In the case of the solution-surface polymerization, the polymerization rate showed maximum as the concentration of the p-toluenesulfonic acid changed at a fixed temsperature or as the temperature was varied at a fixed concentration. The decrease of the polymerization rate with increasing concentration or with rising temperature beyond the values at the maxima is interpreted as resulting from micelle formation.