Surface Properties of Zwitterionic Surfactants

Dahanayake, Mahilal; Rosen, Milton J.

doi:10.1021/bk-1984-0253.ch003

Cited by 16 publications

(6 citation statements)

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“…The CMC values are all around 10 -3 M for y = 12 and 10 -4 M for y = 18. The CMC range of dodecyl compounds is the same as many other zwitterionic amphiphiles reported in the literature [5,[7][8][9][10][11][12][13][14][15][16]. These values are closer to those of ionic surfactants with similar alkyl chains (CMC = 2.10 -2 M for dodecyltrimethylammonium chloride [28]) than with those of polyoxyethylene nonionic ones.…”

Section: Critical Micellar Concentrationssupporting

confidence: 79%

Micellar properties of zwitterionic phosphobetaine amphiphiles in aqueous solution: Influence of the intercharge distance

Chevalier

Germanaud

Perchec

1988

Colloid & Polymer Sci

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Zwitterionic amphiphiles of the general formula H(CH2)y +N(CH3)2(CH2)n PO2C6H~-, where the number of intercharge methylenes n is varied, were studied in dilute aqueous solution. Their critical micellar concentrations show a peculiar variation with n, first increasing as n varies from 1 to 4 and then slowly decreasing as methylenes are added up to 10. This behavior is interpreted as being the consequence of two opposite contributions. The first is the classical CMC lowering due to the increase of hydrophobic character with the total number of methylene groups in the surfactant molecule. The second contribution is the increase in the dipole moment of the zwitterionic headgroup with n, leading to stronger dipole-dipole repulsions between headgroups at the micellar surface. Experimental results suggest that the dipole moment does not increase linearly with n because of the polymethylene chain flexibility. This is supported by 13C NMR relaxation experiments.

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Section: Critical Micellar Concentrationssupporting

confidence: 79%

Micellar properties of zwitterionic phosphobetaine amphiphiles in aqueous solution: Influence of the intercharge distance

Chevalier

Germanaud

Perchec

1988

Colloid & Polymer Sci

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“…If the effect of hydrocarbon length on the variation of the CMC is well known (Klevens, ; Rosen et al, ), it is not the same for the variations of the physicochemical parameters accompanying the micellization. Also the effect of the polar head is often not very well studied and the results of the literature in this area remain scattered (Chevalier et al, ; Dahanayake and Rosen, ; Hajji et al, ; Omar and Abdel‐Khalek, ; Venable and Nauman, ).…”

Section: Discussionmentioning

confidence: 99%

“…On the other hand, only a limited number of publications have been devoted to bifunctional species and the effect of the polar head on micellization. The influence of the size of the hydrophilic part of a quaternary ammonium surfactant on its ability to adsorb at the air/water interface and to form micelles in aqueous media has been reported by many researchers (Dahanayake and Rosen, ; Kabir‐ud‐Din et al, ; Moreira and Firoozabadi, ; Omar and Abdel‐Khalek, ; Shah et al, ; Venable and Nauman, ), but the study of the effect of the localization of a polar group with respect to quaternary nitrogen, N + , has not been widely reported. Let us cite, for example, the work of Chevalier et al (), who studied the effect of the distance between the positive group N + and the carboxylate group on the physicochemical parameters, such as the maximum surface excess Γ m and critical micelle concentration (CMC) of zwitterionic surfactants and also the work in which Hajji et al () showed the effect of the polar head of 2‐(decyldimethylammonio) alkanol bromide surfactants on physiochemical parameters such as the degree of ionization, α , and CMC.…”

Section: Introductionmentioning

confidence: 99%

The Effect of Polar Head and Chain Length on the Physicochemical Properties of Micellization and Adsorption of Amino Alcohol‐Based Surfactants

Hafidi

Achouri

2018

J Surfact & Detergents

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In this work, we have synthesized a series of quaternary ammonium from amino alcohols and n‐bromoalkanes. The compounds are referred to as CnEtOH, CnPrOH, and CniPrOH (where n = 12 and 14 carbons, EtOH = ethanol, PrOH = propanol, iPrOH = iso‐propanol). Their structures were checked using the usual spectroscopic methods [1H, 13C nuclear magnetic resonance (NMR) and infrared (IR)]. Their physicochemical properties in aqueous solution were studied using conductivity, surface tension, and ultra violet (UV)–visible absorption spectroscopy measurements. This study was conducted to show the effect of the linear hydrophobic chain and the location of the OH polar group with respect to the N+ quaternary ammonium on the physicochemical properties of the surfactants. The comparison between the physicochemical properties of the surfactants studied shows a distinct effect of the position of the OH group on the critical micelle concentration (CMC), the ionization degree (α), the area occupied at the interface (Amin), the free energy of adsorption (normalΔGad0), and the free energy of micellization (normalΔGM0). The intermolecular interaction between the synthetic surfactants and the methyl orange (OM) dye is related to the degree of hydration of the micelle, proven by the hypsochromic displacement of OM wavelength (λmax) and ionization (α) of the micelles. The CMC, the degree of ionization, and the degree of hydration of the micelle follow the same trend.

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“…Both tetradecyl trimethylammonium bromide (C 14 TMAB) and the anionic surfactant (C 12 H 25 EO SO − 4 Na + ) were obtained from the Proctor and Gamble Company. The zwitterionic surfactant (C 12 BMG) was synthesized as described earlier (13). Except for C 12 TMAC, all the surfactants were used as obtained.…”

Section: Methodsmentioning

confidence: 99%