Counterion Binding Of Micelles Research Articles

Physicochemical Properties of Noncovalently Constructed Sugar-Based Pseudogemini Surfactants: Evaluation of Linker Length Influence

Natural renewable glucose or lactose upon reaction with dodecylamine has been converted into N-dodecylglucosylamine or N-dodecyllactosylamine, which upon acid–alkali reaction with dicarboxylic acid (HOOC(CH2)n-2COOH, n = 3,4,5,6,8) gives a series of sugar-based pseudogemini surfactants (G-n, L-n, respectively). Some physicochemical properties such as the critical micelle concentration (CMC), equilibrium surface tension at the CMC (γCMC), effectiveness (πCMC), efficiency (pC20), maximum surface excess (Γmax), minimum surface area (Amin), counterion binding of micelles (β), and the changes of standard Gibbs free energy (ΔGm0), enthalpy (ΔHm0) and entropy (ΔSm0) for processes of micellization in the range 298.15 K to 328.15 K have been evaluated by surface tension and electroconductometry methods in aqueous solutions of these pseudogemini surfactants. The results revealed that most of the above properties depend on dicarboxylic acid linker length and headgroup saccharide size. These findings help with unders...

Exploring Physicochemical Interactions of Different Salts with Sodium N-Dodecanoyl Sarcosinate in Aqueous Solution.

Amino acid-based surfactants are used in academics and industry. Sodium N-dodecanoyl sarcosinate (SDDS) is such an amino acid-based surfactant having applications in pharmaceutical, food, and cosmetic formulations. Although the surface properties of this surfactant have been studied in the presence of univalent cationic and anionic salts, there is no report on such solution in the presence of higher valencies. In this experiment, critical micelle concentration (CMC) of SDDS from tensiometry, conductometry, and fluorimetry has been determined. In each case, CMC decreases with increasing salt concentration. Counterion binding of micelles (β), diffusion coefficient (D0), and surface properties, e.g., Gibbs free energy for micellization (ΔGm0), Gibbs surface excess (Γmax), area of exclusion per surfactant monomer (Amin), surface pressure at CMC (πcmc), etc., have been evaluated using methods such as tensiometry, conductometry, and fluorimetry. The hydrodynamic radius of SDDS in the presence of different salts was measured by the light scattering method. Aggregation number and shape of micelle have been determined by small-angle neutron scattering experiment. The nature of amphiphilic packing and the aggregation numbers of the assemblies have also been explored. The results from different experiments have been rationalized and represented systematically.

Thermodynamic and aggregation properties of sodium n-hexylsulfonate in aqueous solution

Thermodynamic and aggregation properties of sodium n-hexylsulfonate (C6H13SO3Na) in aqueous solutions have been studied at different temperatures by density, sound velocity, electroconductivity and vapor–liquid equilibria measurements. The critical micelle concentration (CMC), counterion binding of micelles and thermodynamics of micellization have been evaluated. From the density and sound velocity data, the values of the apparent molar volumes and compressibilities, changes in the apparent molar properties upon micellization and the infinite dilution apparent molar properties of the monomer state of C6H13SO3Na in the aqueous solutions were determined. Vapor–liquid equilibrium data such as water activity, vapor pressure, osmotic coefficient, activity coefficient and Gibbs free energies were obtained through the isopiestic method. A comparison between the mentioned thermodynamic and aggregation properties of C6H13SO3Na in aqueous solutions with those of some other sodium n-alkylsulfonates were also made and from which the effect of the alkyl chain length of the surfactant on the aggregation parameters were examined.

Salt effect on self-aggregation of sodium dodecylsulfate (SDS) and tetradecyltrimethylammonium bromide (TTAB): Physicochemical correlation and assessment in the light of Hofmeister (lyotropic) effect

Amphiphile micellization is a well explored physicochemical process that can be affected by environmental conditions (temperature, pressure and additives). Salts have power to appreciably influence the water activity and self-association of ionic micelles; their effects on physicochemical processes are often examined in terms of Hofmeister or lyotropic series. In this work, physicochemical investigations on the self-association of sodium dodecylsulfate (SDS) and tetradecyltrimethylammonium bromide (TTAB) in aqueous medium in presence of a number of monovalent, bivalent and trivalent inorganic and organic salts at μ = 0.01 at 303 K has been undertaken. Their critical micellar concentration (CMC), counter ion binding of micelles, and energetics of micellization have been estimated by the methods of conductometry and microcalorimetry. The ion effects on the physicochemical parameters have been found to poorly or loosely obey Hofmeister or lyotropic series; for a correlation, the lyotropic number ( L n) has been found to be better than both the effective hydrodynamic radius ( R h) and the polarizability ( α) of the counter ions (cations for anionic SDS micelles, and anions for cationic TTAB micelles).

A critical and comprehensive assessment of interfacial and bulk properties of aqueous binary mixtures of anionic surfactants, sodium dodecylsulfate, and sodium dodecylbenzenesulfonate

The micellization of mixed binary surfactant systems of sodium dodecylsulfate (SDS) and sodium dodecylbenzenesulfonate (SDBS) has been studied by conductometry, tensiometry, fluorimetry, and microcalorimetry at different mole fractional compositions. The counter-ion binding of micelles, micellar aggregation number, thermodynamics of micellization, interaction of components in the mixed micelles, and their compositions therein and amphiphile packing in micelles have been examined. The adsorption features of the surfactants at the air/solution interface have also been estimated. Correlation of the results and explanations of the findings have been presented. The difference in the head groups of SDS and SDBS has manifested interesting solution and interfacial behaviors.

An Approximate Expression for the Degree of Counterion Binding of Dressed Micelles

A simple formula for calculating the degree of counterion binding of dressed micelles is presented. This approximate expression for the spherical micelle is derived from the extending Langmuir's method in the case of high surface potentials. It works quite well for the estimation of the degree of counterion binding of micelles. The simple form is very convenient for practical use.

Micellization and Related Behaviors of N-Cetyl-N-ethanolyl-N,N-dimethyl and N-Cetyl-N,N-diethanolyl-N-methyl Ammonium Bromide

The micellization characteristics of N-cetyl-N-ethanolyl-N,N-dimethyl and N-cetyl-N,N-diethanolyl-N-methyl ammonium bromides have been investigated by microcalorimetric, conductometric, and fluorimetric techniques. The critical micellar concentration (cmc), counterion binding of micelles, their aggregation number, and thermodynamics of micellization have been evaluated at eight different temperatures in the range of 288−323 K. The Gibbs free energy, enthalpy, entropy, and specific heat of the micellization process have been evaluated by the direct calorimetric method as well as by the indirect method of van't Hoff by processing the cmc results of microcalorimetry and conductometry at different temperatures. The differences of the results obtained by these two procedures have been discussed. The thermodynamic results have been compared with values for the parent compound, N-cetyl-N,N,N-trimethylammonium bromide, and the effect of the substitution of the ethanolyl group in place of the methyl group on the s...

Variation of counterion binding in micelles of cetyltrimethylammonium hydroxide

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTVariation of counterion binding in micelles of cetyltrimethylammonium hydroxideHernan Chaimovich, Iolanda M. Cuccovia, Clifford A. Bunton, and John R. MoffattCite this: J. Phys. Chem. 1983, 87, 19, 3584–3586Publication Date (Print):September 1, 1983Publication History Published online1 May 2002Published inissue 1 September 1983https://doi.org/10.1021/j100242a003RIGHTS & PERMISSIONSArticle Views108Altmetric-Citations14LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (362 KB) Get e-Alerts