• Bulletin of the Korean Chemical Society
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• 제10권5호
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• pp.437-442
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• 1989

The cmc's of sodium dodecyl sulfate (SDS)/Triton X-100 surfactant mixtures were determined by surface tension measurement at various surfactant compositions. The cmc values were lower than those predicted from ideal mixture. The regular solution theory was applied to calculate the interaction parameter, micellar composition, and the activity coefficients of surfactants in the mixed micelle. The interaction parameter (${\beta}$) was - 2.1. The nonideality arised largely from decreased activity of SDS in the mixed micelle. The mean aggregation numbers (${\bar{n}}$) and micropolarity of hydrocarbon region of the mixed micelles were determined by luminescence probe techniques. The total aggregation number (${\bar{n}}_{SDS}+{\bar{n}}_{TX}$) in mixed micelles showed little dependency on the composition of the micelle. The apparent dielectric constant of the hydrocarbon region of the micelle vs micellar composition plot showed positive deviation from linearity. Emission and emission quenching of excited tris(2,2'-bipyridine)ruthenium(Ⅱ) cation, $(Ru(bpy)_3^{2+})$, by methylviologen ($MV^{2+}$) were also investigated in the mixed micellar solutions. The quenching rate was lowest when the mole fraction of SDS in the surfactant mixtures (${\alpha}_{SDS}$) is about 0.25 and highest at ${\alpha}_{SDS}$ = 0.85. This was explained in terms of combined effects of binding of the cations with the micelle and mobility of the bound cations on the surface of the micelles.

• Korean Journal of Chemical Engineering
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• 제35권11호
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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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• 제18권2호
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• pp.185-189
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• 1997

The effect of pH and sodium dodecyl sulfate (SDS) micelle on the quenching of Ru(bpy)32+ luminescence by N-alkyl-4,4'-bipyridinium ions (RBPY+: R=methyl, octyl, dodecyl, benzyl) were investigated. In the absence of SDS, the quenching rate at pH 2 is similar to that of the corresponding methylalkyl viologens and much greater than that in pH 8 solution due to greater reducibility of the protonated form of RBPY+ (HRBPY2+). The quenching rate at pH 2 is strongly enhanced by the presence of SDS, while that at basic pH is greatly retarded. These observations are explained by deep embedment of RBPY+ into the hydrophobic hydrocarbon region of the micelle, whereas Ru(bpy)32+ and HRBPY2+ locate in the Stern layer of the micelle.

• 대한화학회지
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• 제38권3호
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• pp.194-199
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• 1994

Sodium dodecylsulfate(SDS) 0.2M수용액 미셀내에 몇 가지 페닐 알카놀$[C_6H_5(CH_2)_nOH;$ 페놀(n=1), 벤질 알코올(n=1), 펜에틸 알코올(n=2), 3-페닐-1-프로판올(n=3)]이 가용화(solubilization)될 때 이들의 가용화 위치를 이차원 이핵 상관 NMR분광법(Two dimensional heteronuclear correlation spectroscopy (2D C-H COSY)으로 조사하였다. 실험 결과 $^1H$-NMR 신호의 적분에 의하여 조사한 이전의 연구결과보다 훨씬 정량적이며 정확한 가용화 위치를 알 수 있었다. 이들이 SDS 미셀 중심의 중간부 메틸렌기에 침투하는 깊이는 ${\alpha}$메틸렌기로부터 6.5~7.0 단위까지 임을 알았다.

• 대한화학회지
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• 제40권6호
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• pp.420-426
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• 1996

순수 물에서 Sodium dodecylsulfate(SDS)와 Sodium dodecylbenzenesulfonate(DBS)로 구성된 혼합계면활성제의 임계미셀농도(CMC) 및 반대이온의 결합상수(${\beta}$)값을 15$^{\circ}C$에서 35$^{\circ}C$까지의 온도범위에서 전도도법으로 측정하였으며, 측정된 CMC 및 ${\beta}$값의 온도에 따른 변화로부터 SDS/DBS 혼합계면활성제의 미셀화에 대한 여러가지 열역학 함수값(${\Delta}C_p,\;{\Delta}G_m^{\circ},\;{\Delta}H_m^{\circ}$ 및 ${\Delta}S_m^{\circ}$)들을 계산하였다. 측정한 온도범위 내에서 SDS/DBS 혼합계면활성제의 미셀화로 인한 ${\Delta}G_m^{\circ}$와 ${\Delta}C_p$의 값들은 모두 음의 값을 그리고 ${\Delta}S_m^{\circ}$값은 모두 양의 값을 나타내었다. 이러한 열역학 함수값들의 온도 및 몰분율조성(${\alpha}_{SDS}$)에 따른 변화를 이용하여 SDS/DBS 혼합계면활성제의 미셀화를 분석하였다.

• 대한화학회지
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• 제55권3호
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• pp.335-340
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• 2011

양이온성 수용성 5, 10, 15, 20-tetrakis(N-methylpyridinium-4-yl) porphyrin (TMPyP)의 존재 하에서 음이온 계면 활성제인 sodium n-dodecyl sulfate 의 용액 특성을 전도도법, UV-vis 및 공명 빛 산란 (RLS) 분광학적 방법을 이용하여 포괄적으로 연구하였다. 그 결과에 따르면 TMPyP 농도의 증가로 SDS 용액의 임계 미셀 농도는 감소하였는데, SDS 미셀의 안정화는 미셀 표면에 존재하는 음전하의 중화 때문이다. SDS용액 내에는 자유 포르피린 단량체, 미셀에 속박된 포르피린 단량체 또는 응집체, 그리고 nonmicellar porphyrin/계면 활성제 응집체와 같은 세 종류의 TMPy종이 분명히 존재하였다. 우리의 연구 결과는 SDS가 TMPyP의 응집을 유도한다는 것을 나타내었다. 실제로 두 종류의 J-aggregations이 관찰되었는데, 하나는 미셀에 속박된 포르피린 단량체 또는 응집체였으며, 다른 하나는 nonmicellar porphyrin/계면 활성제 응집체이다. 그러나, cmc이하에서는 TMPyP가 SDS 음이온과 정전기 상호작용을 나타내었다.

• Bulletin of the Korean Chemical Society
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• 제5권5호
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• pp.182-187
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• 1984

The polarographic and conductometric studies of methyl viologen $(MV^{++})$ solutions with varying concentration of sodium dodecyl sulfate (SDS) showed strong association of $MV^{++}$ and its cationic radical, $MV^+$., with SDS below the critical micelle concentration. The stoichiometries of these associations were found to be their electric charge ratios. Both electrostatic and hydrophobic interactions were found to contribute to the associations. The formation constant of$MV^+.DS^-$ in 0.1 M NaCl was $7{\times}10^3M$. The $MV^{++}$-SDS association was observed to be cooperative leading to formation of large aggregates. In the presence of $MV^{++}$, the micellization of SDS was formation of SDS homo-micelle without direct involvement of $MV^{++}$.

• 대한화학회지
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• 제39권12호
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• pp.896-901
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• 1995

순수 물 및 NaCl의 수용액에서 Sodium Dodecyl Sulfate(SDS)와 Tetraethylene glycol monodode-cyl ether(TGME)의 혼합계면활성제가 $25^{\circ}C$에서 나타내는 임계미셀농도값(CMC$^*$)들을 표면장력계로 측정하였으며, 이들 CMC$^*$값들이 음이온 계면활성제인 SDS의 몰분율 조성(${\alpha}_1$)과 첨과제인 NaCl의 농도에 따라 어떻게 변화하는지를 조사하였다. 유사상태분리모델을 기초로하는 비이상적 혼합비셀모델을 적용함으로써 측정된 CMC$^*$값들로부터 SDS/TGME 혼합계면활성제의 미셀화에 대한 여러가지 열역학적 함수값들을 계산하여 분석하였다.

• Bulletin of the Korean Chemical Society
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• 제27권10호
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• pp.1655-1658
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• 2006

The solution of $[Ru(phen)_2(dppz)]^{2+}$ and SDS has high Resonance Light Scattering (RLS) signals due to $[Ru(phen)_2(dppz)]^{2+}$ assemble on the surface of the SDS micelle. Because of the high affinity ($KB\geq10^6\;L\;mol^{-1}$) between $[Ru(phen)_2(dppz)]^{2+}$ and DNA, the adding of DNA in the solution of $[Ru(phen)_2(dppz)]^{2+}$-SDS makes the dissociation of $[Ru(phen)_2(dppz)]^{2+}$-SDS, and results in decreasing of the RLS signals and increasing of the absorbance. Based on this, a novel method is proposed for DNA assay. Under optimum condition, good linear relationship was obtained within the concentration range of 0.018-1.26 $\mu g\;mL^{-1}$, the linear equation is $I_{RLS}$ = 504.8-348.8 c (c: $\mu g\;mL^{-1}$) and the correlation coefficient (r) is 0.9992. The detect limit for calf thymus DNA is 8.6 ng $mL^{-1}$. The proposed method was successful applied to determine the extracted colibacillus plasmid DNA.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 추계학술발표회
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• pp.183-186
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• 2002

Experiments in the batch soil/aqueous systems were conducted to compare the sorption onto soil and extraction efficiency of sorbed phenanthrene in the presence of the micelle-forming anionic surfactant(SDS) or the micelle-like amphiphilic nano-sized polyurethane particles. Micelle-like amphiphilic nano-sized polyurethane(APU) particles synthesized from amphiphilic urethane acrylate anionomers(UAA) could solubilize phenanthrene within their hydrophobic interiors as the same way that surfactants micelles did in aqueous phase.