• Bulletin of the Korean Chemical Society
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• 제24권10호
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• pp.1444-1448
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• 2003

The microsurface adsorption - spectral correction (MSASC) technique has been applied to the interaction of indigo carmine (IC) with cetyltrimethylammonium bromide (CTAB). The aggregation of IC on CTAB obeys Langmuir isothermal adsorption. The results show that both the monomer complex $IC{\cdot}CTAB$ and the micellar complex $(IC{\cdot}CTAB)_{78}$ were formed. The binding constant of the monomer complex was calculated to be $K_{IC{\cdot}CTAB}$ = 2.20 ${\times}10^5L{\cdot}mol^{-1}$, and the molar absorptivity of the micellar complex was calculated to be ${\varepsilon}_{(IC{\cdot}CTAB)78}\;^{560nm}$ = 8.58 ${\times}10^5L{\cdot}mol^{-1}{\cdot}cm^{-1}$. The aggregation was applied to the determination of cationic surfactant in wastewater.

• 한국응용과학기술학회지
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• 제26권3호
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• pp.370-378
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• 2009

Kinetic studies on the ligand substitution reactions of cyanocomplexes were performed in several micellar solutions. It showed the observed rate constants was found to be independent of the entering ligand concentration at high concentration of cyanopyridine and pyrazinecarboxylate. We could see also that in nonionic and anionic micellar solutions no influence of changes in the surfactant concentration on the observed rate constants was found. Taking into account the hydrophilic nature of the cobalt complex, the cobalt complex molecule was expected to be located in the aqueous phase of the micellar systems, where the reaction would take place. In cationic micellar solutions, a small increase in the observed rate constant was found when the cationic surfactant concentration increased. After reaching a maximum, the rate constant decreased on increasing surfactant concentration and subsequently it reached a plateau, where the observed rate constant was independent of changes in the surfactant concentration.

• Korean Chemical Engineering Research
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• 제46권4호
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• pp.799-805
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• 2008

일반적으로 음이온계면활성제와 양이온계면활성제는 수용액상에서 침전하는 불용성복합물을 형성하기 때문에 상용성이 좋지 않다. 하지만 경우에 따라서 일부 음이온계면활성제와 양이온계면활성제의 1:1 molar complex (catanionic surfactant)는물에용해하면서비이온계면활성제와같이행동하기때문에유사비이온계면활성제복합물(pseudo-nonionic surfactant complex)이라고 부른다. 유사비이온계면활성제복합물은 일반적인 이온성계면활성제에 비해 보다 용이하게 계면에 배열되기 때문에 평형 및 동적 표면장력에서 우수한 계면활성효과를 나타낸다. 계면활성제의 친수성 head group에 polyhydroxyl group을 가진 디글리세릴계 양이온계면활성제인 diglyceryl dodecyl dimethyl ammonium chloride(DGDAC)과 음이온계면활성제 sodium dodecyl sulfate(SDS)를 1:1 molar ratio로 수용액상에서 혼합하였을 경우 molecular interaction parameter ${\beta}^M$가 -17.2로 매우 강한 positive synergism을 보였으며. 평형 상거동과 현미경에 의한 실험결과는 이 DGDAC와 SDS의 혼합수용액은 single phase의 vesicle을 형성함을 알 수 있었다.

• 한국응용과학기술학회지
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• 제33권3호
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• pp.428-434
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• 2016

본 연구에서는 알킬체인의 길이가 서로 다른 benzyltrialkylammonium chloride계 화합물을 합성하여 리포좀 제조에 응용하였다. 제조된 리포좀의 평균 입도분포, 제타전위, 방출거동 및 항균성을 조사하였으며, 사슬 길이에 따른 특성을 비교하였다. 리포좀의 평균 입도는 120~140 nm의 크기분포를 가졌으며 소수성 사슬의 길이가 증가할수록 큰 입자크기를 가졌다. 리포좀 용액의 제타전위는 양이온성 계면활성제인 benzyltrialkylammonium chloride를 첨가함에 따라 +80~90 mV의 값을 가지며 향상된 분산 안정성을 보였다. 방출거동에서는 사슬 길이에 따라 방출 속도를 조절할 수 있었으며 긴 사슬의 계면활성제를 첨가한 리포좀은 증가된 서방형 방출특성을 보였다. 또한, 리포좀의 포집효율은 25.9~27.5% 이었다.

• Environmental Engineering Research
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• 제14권3호
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• pp.153-157
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• 2009

Arsenic at abandoned mine sites has adversely affected human health in Korea. In this study, the feasibility of using cationic surfactant-modified activated carbon (MAC) to remove As(V) was evaluated in terms of adsorption kinetics, adsorption isotherms, and column experiments. The adsorption of As(V) onto MAC was satisfactorily simulated by the pseudo-second-order kinetics model and Langmuir isotherm model. In column experiments, the breakthrough point of AC was 28 bed volumes (BV), while that of MAC increased to 300 BV. The modification of AC using cationic surfactant increased the sorption rate and sorption capacity with regard to As(V). As a result, MAC is a promising adsorbent for treating As(V) in aqueous streams.

• Bulletin of the Korean Chemical Society
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• 제22권9호
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• pp.1009-1014
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• 2001

In aqueous mixtures of cationic OTAC (octadecyl trimethyl ammonium chloride) and anionic ADS (ammonium dodecyl sulfate) surfactants, mixed micelles were formed at low (< 0.2 wt %) total surfactant concentrations. For these mixtures mixed micelliza tion and interaction of surfactant molecules were examined. Mixed critical micelle concentration (CMC), thermodynamic potentials of micellization, and minimum area per surfactant molecule at the interface were obtained from surface tensiometry and electrical conductometry. The mixed micellar compositions and the estimation of interacting forces were determined on the basis of a regular solution model. The CMCs were reduced, although not substantial, and synergistic behavior of the ADS and OTAC in the mixed micelles was observed. The CMC reductions in this anionic/cationic system were comparable to those in nonionic/anionic surfactant systems. The interaction parameter $\beta$ of the regular solution model was estimated to be -5 and this negative value of $\beta$ indicated an overall attractive force in the mixed state.

• 대한화학회지
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• 제37권6호
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• pp.562-569
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• 1993

Dimethyldodecylamine Oxide(DDAO)의 미셀화에 대한 pH 효과와 n-프로판올 효과를 조사하기위하여 유사상태분리모델(pseudophase separation model)을 이용하였다. DDAO는 양성자화된 양이온 계면활성제와 비산성화된 중성 계면활성제 두 종류로 존재할 수 있으며, 이들은 열역학적으로 이성분 혼합메셀을 형성할 수 있다. 각 성분의 조성은 용액의 pH에 따라 달라지며, 각 종류 계면활성제들의 활동도, 미셀상태의 조성, 단량체상태의 조성 및 pH에 따른 임계미셀농도를 유사상태분리이론을 이용하여 실험적인 DDAO의 적정곡선으로부터 계산하였다. 임계미셀농도와 DDAO의 산-염기 해리평형상수($K_a$)는 미셀상태의 조성에 따라 변하였으며, 이들은 pH가 5인 지점에서 최소점 현상을 보이고 있다. 그리고 n-프로판올을 첨가하므로써 DDAO의 임계미셀농도는 감소하였으며, n-프로판올의 농도가 증가할수록 임계미셀농도는 더욱 감소하였다.

• 공업화학
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• 제30권1호
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• pp.17-22
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• 2019

본 연구에서는 소수성 사슬의 길이를 증가시키고 1,4-부탄디올을 스페이서로 사용하여 양이온성 제미니형 계면활성제를 합성하였으며 $^1H-NMR$로 확인하였다. 합성한 계면활성제의 외형은 백색 분말로 나타났으며, Kraffts 점은 $0^{\circ}C$ 이하로 나타났다. 측정된 임계미셀농도(c.m.c)는 표면장력법에 의해 $1.8{\times}10^{-3}{\sim}6.5{\times}10^{-4}mol/L$이었고 표면 장력은 22.5~26.1 dyne/cm이었다. Ross-Miles 방법에 의한 CG 14-6E-14의 초기 거품 높이는 16 cm이었고 5 min 후 높이 14 cm를 나타내어, 가장 좋은 초기 기포력과 기포안정성을 갖는 것을 확인하였다. 또한, 합성한 양이온 제미니 계면활성제와 일반적으로 사용하고 있는 cetyltrimethylammonium bromide (CTAB)의 기포력 및 유화안정성을 비교하였다.

• 한국응용과학기술학회지
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• 제28권2호
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• pp.140-145
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• 2011

Cationic gemini-surfactant, namely 1,4-butane-bis(N-alkanoyloxyethyl-N,Ndimethyl)-diammonium bromide was synthesized and their inhibition effect on corrosion of mild steel in 1 M HCl solution was tested by weight loss method. The synthesized product was confirmed by FT-IR and $^1H-NMR$ spectroscopy. Surface tensions were measured by surface tensiometer Sigma 70. Their c.m.c. values evaluated by surface tension method was $4.1{\times}10^{-5}{\sim}5.4{\times}10^{-5}$ mol/L. The Krafft point of the these surfactants were <0~$10.7^{\circ}C$. The emulsifying properties of synthesized cationic gemini surfactants and sodium dodecyl sulfate (SDS), tetradecyl trimethyl ammonium bromide (TTAB) was investigated. Of these, 1,4-butane-bis(N-lauroyloxyethyl-N,N-dimethyl)- diammonium bromide, CGL 14-4-14 has been confirmed as a good emulsifier. The inhibition efficiency increases by increasing cationic gemini surfactant concentration. As a result, these surfactants are expected to be applied as corrosion inhibitors.

• 한국응용과학기술학회지
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• 제31권1호
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• pp.1-6
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• 2014

Gemini type of cationic surfactant, namely ${\alpha},{\omega}$-alkane-bis(N-lauroyloxyethyl-N,N-dimethyl)-diammonium bromide was synthesized and confirmed by FT-IR and $^1H$-NMR spectroscopy. Their inhibition effect on corrosion of mild steel in 1 M HCl solution was tested by weight loss method. Surface tensions were measured by surface tensiometer Sigma 70. Their c.m.c. values evaluated by surface tension method was $4.01{\times}10^{-5}{\sim}4.99{\times}10^{-5}mol/L$. The Krafft point of the these surfactants were < $0^{\circ}C$. The emulsifying properties of synthesized cationic gemini surfactants and sodium dodecyl sulfate (SDS), tetradecyl trimethyl ammonium bromide (TTAB) was investigated. Of these, ${\alpha},{\omega}$-alkane-bis(N-lauroyloxyethyl-N,N-dimethyl)-diammonium bromide has been confirmed as a good emulsifier. The inhibition efficiency increases by increasing cationic gemini surfactant concentration. As a result, these surfactants are expected to be applied as corrosion inhibitors.