• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.3
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• pp.365-373
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• 1998

The phase behavior of chlorinated hydrocarbon/mixed surfactants/water microemulsion systems were investigated for dry cleaning solvent properties. With appropriate surfactant mixtures, Winsor type I-III-II microemulsions were generated which is the same as hydrocarbon systems. For perchloroethylene(PCE) with mixed Tween systems, the optimum salinity(S*) decreases and the optimum solubilization parameter(o*) increases with decreas- ing HLB. For PCE with mixed Aerosol MA and ethoxylated alcohol systems, S* and o* both increase with increasing ethylene oxide moles. For dichlorobenzene(DCB) with mixed Aerosol MA and ethoxylated or propoxylated sulfate systems, S* and o* both increase with increasing ethylene oxide moles or propylene oxide moles.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.417-421
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• 2003

Three kinds of surfactant systems - cationic surfactant (system 1), combinition of two cationic surfactants (system 2), and combination of two cationic surfactant and non-ionic surfactant (system 3) - for the simultaneous removal of nitrate and phosphate by micellar-enhanced ultrafiltration (MEUF) were investigated. The highest removal efficiencies of nitrate and phosphate were observed in system 2, which were 90 % of nitrate and 72 % of phosphate. The COD of permeate in system 3 was the lowest, because the added non-ionic surfactant made critical micelle concentration (CMC) lower than that of other surfactant systems. In all systems, the flux decline was similar.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.379-384
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• 2011

The critical micelle concentration (CMC) and the counter ion binding constant (B) for the mixed micellizations of DBS (sodium dodecylbenzenesulfonate), SDS (sodium dodecylsulfate), and Brij 30 (polyoxyethylene(4) lauryl ether) at $25^{\circ}C$ in pure water were determined by the use of electric conductivity and surface tension measuring methods. Various thermodynamic parameters ($X_i,\;{\gamma}i,\;C_i,\;a_i^M,\;{\beta}$, and ${\Delta}H_{mix}$) were calculated and compared with each other mixed surfactant system by means of the equations derived from the nonideal mixed micellar model. The results show that the SDS molecule interacts more strongly with Brij 30 molecule than DBS molecule and that the SDS/Brij 30 mixed surfactant system has the greatest negative deviation from the ideal mixed micellar model and the SDS/DBS mixed system has followed almost the ideal mixed micellar model.

• YAKHAK HOEJI
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• v.20 no.3
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• pp.156-161
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• 1976

The salting in and salting out of Octoxynol, N.F., a nonionic polyoxyethylated surfactant by n-alkylamine hydrochlorides ws investigated by measuring their effect on the cloud point of the surfactant at various salt concentrations. The carbon number of the alkyl chain was varied from zero to twelve. Ammonium chloride, methylamine hydrochloride and ethylamine hydrochloride tended to salt out the surfactant, lowering its cloud point in proportion to the salt concentration. n-Ankylamine and n-butylamine hydrochlorides showed salting-out effect at low concentrations of the electrolyte, while their effects were leveled off and showed rather salting-in trend at higher concentrations of the electrolyte. These salting-in effect was ascribed to the formation of a hydrotropy of the n-alky lammonium cations with the surfactant. The higher homolog compounds of n-alkylamine hydrochlorides showed extraordinarily high salting-in effect at very low oncentrations of the electrolyte. These large salting-in effects were more drastic as the chain length was getting longer. These large increases of the cloud point of the surfactant were attributed to the formation of mixed micelles of n-alkylammonium cations with the polyoxyethylated surfactant.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.330-342
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• 2003

The formation of emulsions and micelles in water/ceramide PC104/CholE $O_{20}$/C$_{16}$E $O_{20}$ and water/ceramide PC104/CholE $O_{20}$ mixtures was investigated through the phase behavior studies. The phase diagrams showed the existence of micelle and emulsion regions in both systems. The mixed surfactant system (CholE $O_{20}$/C$_{16}$E $O_{20}$) showed the wider micellar and emulsion regions than the single surfactant system (CholE $O_{20}$). From FT-IR measurements, it was found that the polyoxyethylene (POE) groups of surfactants formed the hydrogen bonds with amido carbonyl group in ceramide PC104. This result indicated that the hydrophilic part (EO) of surfactants could stabilize the lamellar structure and emulsion of ceramide PC104. The mixed surfactant system (CholE $O_{20}$/C$_{16}$E $O_{20}$) resulted in the smaller emulsion droplet size due to the effect of curvature at the interface, thus further increasing emulsion stability. With the penetration of $C_{16}$E $O_{20}$into the interfacial layer of surfactants in emulsion, the curvature of the interface might be altered for the formation of smaller emulsion droplets. The mixed surfactant system could incorporate up to 4 wt. % of ceramide PC104 into emulsion more than single surfactant system.ystem.m.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.96-98
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• 2000

Column experiments were peformed to evaluate the efficiency of surfactant flushing for remediation of non-aqueous phase liquid (NAPL) in the soil under controlled conditions. In column experiment less than 0.1 % of the original mass of tetrachloroethylene (PCE), remained in the column after 15 pore volumes of 1% sorbitan monooleate solution were passed through columns. To determine the influence of soil parameters that may affect the remediation process, column tests were repeated with different values of grain size, application rate, surfactant type, surfactant concentration, and solution viscosity (polymer mixed with surfactant). Experimental works suggest that surfactant flushing has a great potential to rapidly remove mass from NAPL in the soil.

• Journal of the Korean Society of Clothing and Textiles
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• v.18 no.3
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• pp.348-354
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• 1994

The changes of surface activities in the aquaous solutions of mixed surfactants composed of linear sodium dodecylbenznesulfoate (LAS), polyoxyethylene nonyl phenylether (PE, EO=10) and polyethylene glycol monolauryl ether (LE, EO=25) have been studied. Addition of nonionic surfactants to LAS reduces the surface tension, especially at the lower concentration than cmc. The interfacial tension of olive oil/LAS was lower than the other surfactant solutions. The removal of triolein from cotton fabrics by nonionic surfactants and mixtures is higher than by LAS. The addition of NaCI to surfactant solutions even though reduces surface tension smaller but enthances oil removal more than that of $CaCl_2$.

• Korean Journal of Chemical Engineering
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• v.35 no.11
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• pp.2269-2282
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• 2018

Mixed micelle formation behavior of cationic surfactant-cetyltrimethylammonium bromide (CTAB) and anionic surfactant sodium dodecyl sulfate (SDS) in aqueous as well as in urea medium from 303.15 K to 323.15 K at 5 K interval was carried out by conductometric method. The differences between the experimental values of critical micelle concentrations (cmc) and ideal critical micelle concentrations ($cmc^{id}$) illustrate the interaction between the amphiphiles studied. The values of micellar mole fraction ($X_1^{Rub}$ (Rubingh), $X_1^M$ (Motomura), $X_1^{Rod}$ (Rodenas) and $X_1^{id}$(ideal) of surfactant CTAB determined by different proposed models and outcome indicate high involvement of CTAB in SDS-CTAB mixed micellization, which enhance by means of the augment of mole fraction of CTAB. The negative value of interaction parameter (${\beta}$) showed an attractive interaction involving CTAB and SDS. Activity coefficients were less than unity in all case, which also reveals the presence of interaction between CTAB & SDS. The negative ${\Delta}G^0_m$ values imply the spontaneous mixed micellization phenomenon. The attained values of ${\Delta}H^0_m$ were positive at inferior temperature, while negative at superior temperature. The negative ${\Delta}H^0_m$ values in urea ($NH_2CONH_2$) medium illustrate exothermic micellization process. The magnitudes of ${\Delta}S^0_m$ were positive in almost all cases. The excess free energy of mixed micelle formation (${\Delta}G_{ex}$) was found to be negative, which indicates the stability of mixed micelle as compared to the individual's components micelles.

• Bulletin of the Korean Chemical Society
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• v.26 no.1
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• pp.107-114
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• 2005

Molecular aggregates of surfactant molecules consisting of one or more bilayers arranged in a hollow, closed, usually spherical geometry are termed “esicles”or “iposomes” In recent years it has been found that in certain systems the vesicular structure forms spontaneously and is long lived, and it has been suggested that these structures may in fact constitute the equilibrium state in these cases (as is true of micelles) This paper deals with the mixed CMC, vesicles, phase behavior, phase transition, geometrical structure, their formation and characterization in the aqueous solutions of mixed cationic/anionic surfactants systems. TEM micrographs revealed that the vesicles were of spherical shape and that their size was of around 180 nm. The zeta potentials are positive at CGS1-rich regions and negative at SLES-rich regions. In the region where SLES/CGS1 (6/4), the zeta potentials are very small, implying that the vesicles at this surfactant ratio may be less stable. At other surfactant ratios, the vesicles are thought to be stable, supported by large absolute values of zeta potentials and little change in UV absorbance for several months.

• Journal of the Korean Applied Science and Technology
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• v.27 no.1
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• pp.87-92
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• 2010

Silicone surfactants are widely used in many industrial area because of its thermal stability and lower foaming property. But it has limitation to expand the application because of migration and bubble generation issues when it is mixed with organic surfactant. In this study, epoxy functionalized fluoro-silicone surfactant, perfluoro glycidoxypropyl polyether siloxane(PFGES), was synthesized using hydrosilylation reaction among perfluoro methyl hydrogen siloxane, allyl glycidyl ether, and allyl ployether in order to get lower surface tension, better thermal stability than conventional silicone surfactant, and reactivity with anhydride function.