Degree Of Counterion Dissociation Research Articles

Effect of Cosolvents DMSO and Glycerol on the Self-Assembly Behavior of SDBS and CPC: An Experimental and Theoretical Approach

The study of the effect of cosolvents on the micellization of ionic surfactants is relevant in different industrial applications. In this article, we studied the effects of binary aqueous mixtures of DMSO and glycerol on the micellization and thermodynamic behavior of sodium dodecyl benzenesulfonate (SDBS) and cetylpyridinium chloride (CPC) in the range of (293.15–308.15) K. The electrical conductivity method was employed to determine the parameters of micellization such as the critical micellar concentration (CMC) and degree of counterion dissociation (α). The temperature dependence of CMC values was used to calculate other thermodynamic parameters of micellization such as the standard free energy of micellization (ΔGm0), the standard enthalpy of micellization (ΔHm0), and the standard entropy of micellization (ΔSm0). Result analysis showed that the CMCs of both surfactants (SDBS and CPC) were directly proportional to the cosolvent concentration. The standard free energy of micellization (ΔGm0) was negati...

Improved Synthesis and Properties of N-(3-octadecylamino-2-hydroxyl) Propyl Trimethyl Ammonium Chloride

AbstractThe cationic surfactant, N-(3-octadecylamino-2-hydroxyl) propyl trimethyl ammonium chloride was synthesized by an improved synthesis method and the structure was confirmed by Mass Spectrometry and 1H NMR Spectrometry. The physiochemical properties of the product were investigated systematically by surface tension and conductivity measurements. Various physiochemical parameters were calculated to evaluate the surface activities of the surfactant. The results show that both the critical micelle concentration and the degree of counterion dissociation increased with increasing temperature, but the surface tension at CMC decreased, which is opposite to that obtained on the previous condition with increasing NaCl concentration. The thermodynamic parameters obtained from conductivity measurement show that the micelle formation of the surfactant is entropy-driven in the investigated temperature range. While used as an asphalt emulsifier, N-(3-octadecylamino-2-hydroxyl) propyl trimethyl ammonium chloride exhibited an excellent emulsifying ability and it was a medium-set asphalt emulsifier.

Surface Activity, Adsorption, and Micellization Parameters of Ammonium Surfactants Containing a Hydroxyethyl and Hydroxyisopropyl Head Group

On the basis of measurements of conductivity and surface activity, adsorption and micellization parameters such as critical micellization concentration (CMC), adsorption efficiency, effectiveness of surface tension reduction, and a degree of counterion dissociation (α) for four new ammonium surfactants, octyl-N-(2-hydroxyethyl)-N-(2-hydroxypropyl) ammonium chloride, nonyl-N-(2-hydroxyethyl)-N-(2-hydroxypropyl) ammonium chloride, dodecyl-N-(2-hydroxyethyl)-N-(2-hydroxypropyl) ammonium chloride, and hexadecyl-N-(2-hydroxyethyl)-N-(2-hydroxypropyl) ammonium chloride in aqueous solutions have been determined. The values of CMC determined by two different methods are compared, and they show reasonable agreement. Using the results of electroconductometric and tensiometric measurements, enthalpy (ΔH), the Gibbs free energy (ΔG), and entropy (ΔS) for processes of adsorption and micellization have been computed. The influence of the length of the alkyl chain in the synthesized salts on surface activity and thermod...

Influence of methanol and dimethyl sulfoxide and temperature on the micellization of cetylpyridinium chloride

The micellar behavior of cetylpyridinium chloride (CPC) in water and polar non-aqueous solvents has been investigated in the temperature range of 298.15–323.15K using conductivity methods. The specific conductivity versus concentration plot determines the micellization parameters using critical micelle concentration (CMC) and degree of counter-ion dissociation (α) of the micelle. It was observed that the micellization tendency of the surfactant decreases in the presence of solvents.Thermodynamic properties such as the standard free energy of micellization (∆Gmo), the standard enthalpy of micellization (∆Hmo), the standard entropy of micellization (∆Smo), the standard free energy of transfer (∆Gtranso) and the heat capacity of micellization (∆mCp°) of CPC are significantly affected by the addition of methanol and dimethyl sulfoxide (DMSO). The solvophobic parameter characterized by the Gibbs energy of transfer of hydrocarbons from gas into a given solvent can be used to account for the effect of methanol and DMSO on the formation and growth of the CPC aggregate in water.

Aggregation properties and thermodynamics of micellization of gemini surfactants with diamide groups and rigid spacers in water and water-organic solvent mixed media

The aggregation behavior and thermodynamics of micellization of three gemini surfactants with diamide groups and rigid spacers in various volume percentages of ethylene glycol (EG-WR) and three different types of 10% organic co-solvents (MA-WR, DMF-WR and AN-WR) across a range of temperature from (281.15 to 331.15) K, have been investigated by electrical conductivity measurements. The properties parameters including critical micelle concentration (CMC), degree of counter ion dissociation (α) were determined and discussed. The thermodynamic parameters of micellization including standard Gibbs energy (ΔG°m), Gibbs energy of transfer (ΔG°trans), Gibbs energy of micellization per alkyl tail (ΔG°tail), standard enthalpy (ΔH°m) and standard entropy (ΔS°m) were calculated from the temperature dependence of the CMC and α values. With the increasing chain length, the CMC of gemini surfactants decreased. At a given temperature, The CMC and α values are found to increase with the increasing percentage of EG content in the mixed solvent. The temperature dependence of ΔG°m and CMC values for the gemini surfactants in all the investigated systems is U-shaped. Compensation of enthalpy and entropy of micellization of all three gemini surfactants were observed in all the studied mixed media.

Self-aggregation of ionic liquid-cationic surfactant mixed micelles in water and in diethylene glycol–water mixtures: Conductometric, tensiometric, and spectroscopic studies

Interaction of imidazolium based surface-active ionic liquid (SAIL), 1-decyl-3-methylimidazolium chloride [C10mim][Cl], with cationic surfactant cetrimide (CET) has been studied by using conductometric, tensiometric, and spectroscopic methods in pure water and in presence of diethylene glycol (DEG)–water binary mixtures. Addition of DEG has marked effect on the thermodynamic and aggregation behavior of these studied systems. From conductometric approach various parameters have been calculated such as critical micelle concentration, (cmc), micellar mole fraction, X1, of component 1 (CET), micellar interaction parameter, β, activity coefficients ƒ1 and ƒ2 of component 1 and component 2 (SAIL), standard Gibbs energy of micellization (ΔGm0), and degree of counter ion dissociation (g). Rubingh's non-ideal solution theory confirms the attractive and non-ideal behavior among the surfactant molecules in the mixed micelles. From the tensiometric studies different parameters such as surface tension reduction efficiency (pC20), maximum surface excess concentration (Γmax), minimum area per surfactant molecule (Amin) and standard Gibbs free energy of adsorption ΔGad0 at the interface were evaluated. The packing parameters of amphiphiles in the micelles, P, volume contribution of the hydrophobic chain, v, and its effective length, lC have also been evaluated for the pure and mixed systems. The micelles/mixed micelles formed have spherical geometry. Cresol red, an anionic dye, was used as a probe for UV–visible spectra of pure and mixed systems, which supports the role of SAIL in the mixed micellization process.

Effect of Amino Acids and Glycyl Dipeptides on Micellization of Antibacterial Drug Domiphen Bromide

AbstractThe effects of amino acids (glycine, l‐alanine, l‐valine, l‐leucine) and glycyl dipeptides (glycylglycine, glycyl‐l‐valine, glycyl‐l‐leucine) on the micellization behaviour of antibacterial drug domiphen bromide in aqueous solution as a function of temperature were studied by both conductivity and fluorescence spectroscopy. Critical micellar concentration, degree of counterion dissociation (α), limiting molar conductivity (Λ0), and a series of thermodynamic parameters of micellization of domiphen bromide have been calculated from the specific conductivity data. The I1/I3 ratios associated with pyrene fluorescence vibronic bands were used to interpret the variation of micropolarity caused by the interactions between domiphen bromide and amino acids/glycyl dipeptides. The mean aggregation number of domiphen bromide was determined by a fluorescence quenching method. Effects of temperature, concentration, and alkyl chain length of the amino acids/glycyl dipeptides on the above properties were examined. Amino acids and glycyl dipeptides effectively enhance the surface activity of domiphen bromide solution. The intensity of amino acid/dipeptide‐domiphen bromide interaction increased with the hydrophobicity of the amino acid/glycyl dipeptide.

A Mathematical Approach to a More Accurate Determination of Critical Micelle Concentration and Other Thermodynamic Parameters of 14‐2‐14 Gemini Surfactant in Water–Organic Solvent Mixed Media at Variable Temperatures

AbstractTo explore how the solvent characteristics influence the self‐aggregation of the cationic gemini surfactant dimethylene‐1,2‐bis(tetradecyldimethylammonium bromide) (14‐2‐14) and to obtain various energetic parameters, conductometric experiments were performed on the binary mixtures in the presence of commonly used organic solvents; formamide (FA), acetonitrile (AN) and 2‐methoxyethanol (ME) in aqueous solutions at varying temperatures (298.15–323.15 K) and compositions. The procedure suggested by Carpena et al. has been utilized to analyze conductivity–concentration plots in order to obtain critical micelle concentration (CMC) and degree of counterion dissociation (α) of the micelles. This method provides more accurate results as compared to conventional treatments, and the experimental error for the evaluation of micellar parameters is reduced significantly. The results revealed that, although the process of micellization becomes less favorable with the increase in composition of FA, AN and ME in mixed systems, the increase in CMC at compositions lower than 20% (v/v) of the organic solvents is relatively less, indicating that water character is dominant in the bulk phase. As the enthalpy of micellization became more negative, the corresponding entropy change became less positive and enthalpy–entropy compensation phenomenon has been observed for 14‐2‐14 in all the mixtures within the studied temperature range.

Aqueous solution behavior of cationic surfactant modulated by glycol additives: Investigating aggregation and microstructure of tetradecyltrimethylammonium bromide micelles in the presence of propylene glycol, its ethers and esters

The effect of propylene glycol (PG), its monoalkyl ethers and esters on the micellar behavior of a cationic surfactant tetradecyltrimethylammonium bromide (TTAB) in aqueous solution was examined by employing electrical conductivity and small angle neutron scattering (SANS) technique. From conductivity measurements critical micelle concentration (CMC) and degree of counter ion dissociation (α) were evaluated. PG and propylene glycol monomethyl ether (PGMME) delayed micelle formation while propylene glycol monobutyl ether (PGMBE) propylene glycol monomethyl ether acetate (PGMMEA) and propylene glycol diacetate (PGDA) favored the process at studied concentrations. SANS data revealed the effect of all these additives for 100mM TTAB; decrease in micelle size and aggregation number (Nagg) was observed. Results are discussed in terms of effect of additives on water structure and solvent properties and correlated with structure of additives and their octanol-water partition co-efficient values (log Po/w).

Effect of 1-ethyl-3-methylimidazolium bromide on interfacial and aggregation behavior of mixed cationic and anionic surfactants

Aggregation behavior and interaction of sodium dodecyl sulfate (SDS), tetradecyl trimethyl ammonium bromide (TTAB) and their mixtures with an excess of anionic surfactant in the presence of imidazolium-based ionic liquid, 1-ethyl-3-methylimidazolium bromide (EMIm Br) were investigated using surface tension, electrical conductivity, dynamic light scattering (DLS), transmission electron microscopy (TEM) and cyclic voltammetry measurements. Different physicochemical properties such as critical micelle concentration (CMC), degree of counterion dissociation (αdiss), interfacial properties, the standard Gibbs energy of adsorption and the size of aggregates were determined. The effects of ionic liquid (IL) as additive on the interactions between the surfactants; TTAB, SDS and their mixtures were analyzed on the basis of regular solution theory, both for mixed monolayers at the air/liquid interface (βδ) and for mixed micelles (βM). Interaction parameter values suggested that the formation of aggregates is due to the synergistic interactions in the case of SDS/TTAB systems and becomes more affected by adding IL. It was shown that an excess of cationic surfactant and IL resulted in an increase in the nano-aggregate sizes. The synergism observed for three component systems (surfactant–water–IL) revealed the effect of attractive electrostatic interaction, formation of a three-dimensional hydrogen bond network and hydrophobic forces on mixed micelle formation.

Effect of ethylene glycol and propylene glycol on the aggregation of alkanediyl-α,ω-bis(tetradecyldimethylammonium bromide) (14–s–14; s = 4–6) gemini surfactants

The effect of addition of two co-solvents (ethylene glycol (EG) and propylene glycol (PG)) on the aggregation properties of three cationic gemini surfactants (viz. butanediyl-1,4-bis(tetradecyldimethylammonium bromide) (14–4–14), pentanediyl-1,5-bis(tetradecyldimethylammonium bromide) (14–5–14) and hexanediyl-1,6-bis(tetradecyldimethylammonium bromide) (14–6–14)) has been studied by conductance, steady state fluorescence and dynamic light scattering measurements at 298K. The weight percentage of these co-solvents varied in between 0 and 50% at an interval of 5% up to 20% and then 10% up to 50%. Micellization is delayed by the addition of co-solvents; consequently, a progressive increase was observed in critical micelle concentration (cmc) and Gibbs free energy of micellization (ΔGm0), a rough increase was observed in the values of degree of counter ion dissociation (α) and a decrease was obtained in values of average aggregation number (Nagg) and Stern–Volmer constant (KSV). At low weight percentage (up to 15%) of co-solvents, 14–s–14 (s=4–6) geminis are found to be almost equally prone to micellization both in EG–water (EG–WR) and in PG–water (PG–WR) mixed media whereas at high weight percentages they are more prone to micellization in EG–WR than in PG–WR mixed media. The measurements of hydrodynamic radius (dH) performed at a concentration of 10mmolkg−1 shows that the hydrodynamic diameter (dH) is less than 70nm for most of the system except at some of the composition where slightly higher values were obtained.

Synthesis and Physico‐Chemical Properties of Sodium 3‐Oxo‐2‐(3‐(4‐sulphonatophenyl)triaz‐2‐enyl)octadecanoate Anionic Surfactant

AbstractThe novel anionic surfactant sodium 3‐oxo‐2‐(3‐(4‐sulphonatophenyl)triaz‐2‐enyl)octadecanoate (SSTO) was prepared from renewable raw materials; glycine and palmitic acid. Surface and bulk properties of SSTO were investigated by surface tension and electrical conductivity techniques at 298, 308, 318 and 328 K. Surface properties including critical micelle concentration (CMC), maximum surface excess concentration (Γmax), minimum area per molecule (Amin), surface tension at CMC (γCMC), effectiveness of surface tension reduction (ΠCMC), efficiency of surface adsorption (pC20), and degree of counterion dissociation (α) were determined. The thermodynamic parameters of micellization (ΔG°mic, ΔH°mic and ΔS°mic) and adsorption (ΔG°ad, ΔH°ad and ΔS°ad) were also investigated at 298, 308, 318 and 328 K. The effect of 3 wt% n‐propanol, n‐butanol and n‐pentanol on surface tension and conductivity at 298 K was also determined.

Influence of organic solvents and temperature on the micellization of conventional and gemini surfactants: a conductometric study

ABSTRACTThe micellar behaviour of similar hydrophobic chain length conventional (cetyltrimethyl ammonium bromide, CTAB; cetyl pyridinium chloride, CPC; cetyldimethylbenzyl ammonium chloride, C16BCl) and gemini surfactant (16-2-16) in water and polar non-aqueous solvents has been investigated in the temperature range 288.15–318.15 K with the help of conductivity measurements. The method proposed by Carpena et al. has been used to analyse the conductivity–concentration to determine the micellization parameters using critical micelle concentration (CMC) and degree of counter-ion dissociation (α) of the micelle. It shows much better performance than the conventional methods and the effect of experimental errors on the evaluation of the micellization parameters has been shown to be minimal by using this procedure. It was observed that the micellization tendency of the surfactant decreases in the presence of solvents. Thermodynamic parameters were also evaluated from the temperature dependence of the CMC values.

Interaction of hexadecylpyridinium bromide with glycine in aqueous medium using the Krafft temperature from conductivity measurement

Conductivity measurements were employed to investigate Kraft temperature (TK) of aqueous solution of hexadecylpyridinium bromide (HPyBr) and HPyBr+glycine with added counter-ions. The pseudophase ion exchange model was adopted for HPyBr in pure water, glycine (Gly) and potassium bromide (KBr). The TK values for HPyBr increase with the increase in concentration of Gly and KBr. However, the experimental results show that the degree of counter-ion dissociation or ionization (α) remains nearly constant as the total surfactant concentration or counter-ion concentrations of salt are varied at the slower rate of micellar growth. Although the (α) is dependent on micellar shapes and changes as the micellar shape changes. The TK measurements for ionic micelles can be used to estimate counter-ion dissociation (α). The TK increase with increase in the counter-ion concentration because the solubility of surfactant is reduced at faster rate than critical micellar concentration (CMC). Kraft temperature measurements were employed to find the interaction between HPyBr and Glycine.

Solvation dynamics and rotational relaxation of coumarin 153 in mixed micelles of Triton X-100 and cationic gemini surfactants: effect of composition and spacer chain length of gemini surfactants.

Solvation dynamics and rotational relaxation of coumarin 153 (C-153) in mixed micelles of non-ionic surfactant, Triton X-100 and a series of cationic gemini surfactants, 12-s-12, 2Br with varying polymethylene spacer chain length (s = 3, 6, 8, 12) at different bulk mole fractions of a surfactant were studied. Studies were carried out by means of UV-Vis absorption, steady-state fluorescence and fluorescence anisotropy, time-resolved fluorescence and fluorescence anisotropy, and dynamic light scattering measurements. While micropolarity of the environment around C-153 in mixed micelles increased, the microviscosity decreased with increasing amount of a gemini surfactant. This is because the thickness of the Stern layer of micelles increases as a result of greater extent of penetration of water molecules. Solvation dynamics and rotational relaxation of C-153 become faster with increasing mole fraction of a gemini surfactant in the mixed micelles. Increasing the thickness of the Stern layer leads to an increase in the number of water molecules hydrogen bonded among themselves, resulting in an increase in polarity and microfluidity of the environment. At a given bulk mole fraction of a surfactant, the microviscosity of micelles decreases with increasing the spacer chain length of the gemini surfactant resulting in an increase in the rate of the rotational relaxation process. However, at a given bulk mole fraction of a surfactant, solvation dynamics becomes slower with increasing spacer chain length from s = 3 to 8 because of the increasing degree of counter ion dissociation. The slow rotational relaxation process is mainly due to the lateral diffusion of C-153 along the surface of the micelles. Rotationalmotion of the micelle as a whole is much slower than the lateral diffusion of C-153.

Effect of Polymethylene Spacer of Cationic Gemini Surfactants on Solvation Dynamics and Rotational Relaxation of Coumarin 153 in Aqueous Micelles.

The present work demonstrates the solvation dynamics and rotational relaxation of Coumarin 153 (C-153) in the micelles of a series of cationic gemini surfactants, 12-s-12, 2Br(-) containing a hydrophobic polymethylene spacer with s = 3, 4, 6, 8, 12. Steady-state and time-correlated single-photon counting (TCSPC) fluorescence spectroscopic techniques have been used to carry out this study. Steady-state and TCSPC fluorescence data suggest that C-153 molecules are located at the Stern layer of micelles. While probe molecules feel more or less the same micropolarity in the micellar phase, the microviscosity of micelles decreases with spacer chain length. Solvation dynamics at the Stern layer is bimodal in nature with fast solvation as a major component. Counter ions and water molecules bonded with the polar headgroups of surfactant molecules are responsible for the slow component. Average solvation time increases with spacer chain length because of the increased degree of counter ion dissociation. Some water molecules are involved in the solvation of counter ions themselves, resulting in the decrease in "free" water molecules to be available for the solvation of C-153. The hydrophobic spacer chain also has an effect on increasing the solvation time with increasing chain length. The average rotational relaxation time for C-153 decreases with spacer chain length with a rapid decrease at s > 4. The anisotropy decay of C-153 in micelles is biexponential in nature. The slow rotational relaxation is due to the lateral diffusion of C-153 in micelles. Lateral diffusion is much faster than the rotational motion of a micelle as a whole. The rotational motion of the micelle as a whole becomes faster with the decreasing size of micelles.

English

Surface physico-chemical and thermodynamic studies of some aqueous surfactant solutions were carried out by employing conductance, surface tension and dye solubilization (UV-Vis absorption spectroscopy) techniques. From conductivity and surface tension measurements, critical micelle concentration (CMC), counter-ion association constant (α), equivalent conductance at infinite dilution (λo), surface exess concentration (Гmax ), minimum area per molecule (Amin), surface pressure at CMC (πCMC), thermodynamic properties of micellization (∆Gomic, ∆Homic, ∆Somic) and adsorption (∆Goads, ∆Hoads, ∆Soads) have been obtained for an anionic (sodium dodecyl sulphate (SDS)), a cationic (hexadecyl trimethyl ammonium bromide (HTAB)) and nonionic (Polyoxyethylene (20) sorbitan mono-oleate (Tween 80)) surfactant solutions. Effect of mixing cosolvents (1,2-Ethanediol or 1,2,3-Propanetriol) on physico- chemical properties of surfactant systems at 298.15, 308.15 and 318.15K has been investigated. Surfactants micellar characteristics and their interactions with cosolvents were also investigated by Uv-vis absorption spectroscopy measurements of solutions using bromothymol blue as a probe. The inclusion of cosolvents caused an increase in CMC and degree of counterion dissociation (β) of surfactant solutions whereas the thermodynamic analysis shows that, although the micellization is less favorable in mixed solvent compared to pure water, the process is spontaneous and exothermic.   Key words: Conductance, dye solubilization, micellization, surface physico-chemical properties.

Thermodynamic and aggregation behavior of aqueous tetradecyltrimethylammonium bromide in the presence of the hydrophobic ionic liquid 3-methyl-1-pentylimidazolium hexafluorophosphate

The micellization behavior of the cationic surfactant, tetradecyltrimethylammonium bromide (TTAB) with the ionic liquid (IL) 3-methyl-1-pentylimidazolium hexafluorophosphate [C5mim][PF6] has been investigated using conductometric and spectroscopic techniques. Addition of different wt.% of [C5mim][PF6] to aqueous TTAB solution results in an increase in cmc as well as a decrease in aggregation number (Nagg). The cmc and degree of counterion dissociation (α) of the aqueous solution of TTAB containing different amounts of [C5mim][PF6] have been determined at various temperatures by means of electrical conductivity. The two popular solvatochromic fluorescence probes pyrene and pyrene-1-carboxaldehyde have been used in order to confirm cmc and to calculate Nagg. The preferential site of localization of IL molecules in TTAB micelles was assessed using 1H NMR spectroscopy. In general, [C5mim][PF6] shows an inhibitory effect on the formation of micelles of TTAB and leads to an increase in cmc. The results obtained through conductance measurements are well supported by spectral studies, viz. fluorescence and NMR.

Conductometric Studies on Micellization of Cationic Surfactants in the Presence of Glycine

Values of the critical micelle concentration (cmc) and degree of counterion dissociation (α) of four cationic surfactants: cetyltrimethylammonium bromide (CTAB), cetylpyridinium bromide (CPB), cetylpyridinium chloride (CPC) and benzyldimethylhexadecylammonium chloride (BDHAC) in aqueous–glycine medium (concentration of glycine (Gly) varied from 0 to 0.20 mol·dm−3) were determined through conductometric measurements at 303 K. The effect of temperature on the micellization in the presence of 0.10 mol·dm−3 Gly were studied for the surfactants CTAB, CPC and BDHAC. With respect to the concentration of Gly, a decrease in the cmc was observed for CTAB, CPC and CPB whereas an increase was observed for BDHAC. A regular increase in α was obtained for CPB, CPC and BDHAC with respect to the concentration of Gly whereas values were roughly constant in the case of CTAB. Thermodynamic parameters were computed from the temperature dependence of the cmc values and it was found that the micellization process is exothermic. Compensation of enthalpy and entropy was observed for the micellization of CTAB, CPC and BDHAC in the presence of 0.10 mol·dm−3 Gly.

Micellization and Surface Properties of Alkanediyl-1,4-bis(tetradecyldimethylammonium Bromide) Gemini Surfactants with Dodecylethyldimethylammonium Bromide

Mixed micellization and surface properties of three cationic gemini surfactants, viz., (butanediyl-), (pentanediyl-), (hexanediyl-)-1,4-bis(tetradecyldimethylammonium bromide) (14-s-14; s = 4–6) with dodecylethyldimethylammonium bromide have been studied by conductometric, tensiometric, and fluorimetric techniques at 298 K. Values of cmc, ideal cmc(cmc*), degree of counter ion dissociation (g), micellar mole fractions of the components, and interaction parameters have been determined. Further, activity coefficients of the components, surface excess concentration (Γmax), minimum surface area per molecule (Amin), surface pressure at the cmc (πcmc), average aggregation numbers of the micelles (Nagg), excess Gibbs free energy (), and Gibbs free energy of micellization () were also calculated and discussed. The compositions of the mixed systems were varied between 0 and 1. It is observed that the values of cmc, g, , , and Γmax decreases whereas Amin increases with augmentation of 14-s-14 (s = 4–6) mole fraction in the mixed systems. The negative values of interaction parameters (βσ and βm) obtained for mixed micelle formation indicate attractive interaction between the components leading to nonideality. The nonideal behavior has been theoretically treated by Clint's and Rubingh's model in light of regular solution theory.