Sulfonate Gemini Surfactants Research Articles

Interfacial Dynamic Properties and Dilational Rheology of Sulfonate Gemini Surfactant and its Mixtures with Quaternary Ammonium Bromides at the Air–Water Interface

AbstractThe dynamic interfacial properties and dilational rheology of gemini sulfonate surfactant (SGS) and its mixtures with quaternary ammonium bromides (DTAB, CTAB) at the air–water interface were investigated using drop shape analysis. Results suggest that the adsorption process of these surfactants is diffusion‐controlled at dilute concentrations, whereas the adsorption mechanism gradually shifts to a mixed kinetic‐diffusion control with increasing surfactant concentration. The mixed surfactant system possesses the best surface activity when the molar ratios of SGS/DTAB and SGS/CTAB mixtures are 9:10. The formation of catanionic complexes shields the electrostatic repulsion between surfactant molecules and lowers the electrostatic adsorption barrier. Therefore, SGS/DTAB and SGS/CTAB mixtures exhibit higher adsorption rates than either component alone. The effects of oscillating frequency and surfactant concentration on the surface dilational properties of SGS, DTAB, CTAB, SGS/DTAB, and SGS/CTAB mixtures were also determined. As the oscillating frequency increases, the dilational elasticity of these surfactants gradually increases. The dilational elasticity peaks at a certain concentration, which is less than the critical micelle concentration (CMC). Results show that the dilational elasticity of SGS/DTAB and SGS/CTAB mixtures is higher than that of either component, resulting from the formation of a denser monomolecular adsorption layer at the air–water interface. Our study provides a basis for understanding the interaction mechanism of catanionic surfactant mixtures containing Gemini surfactant at the air–water interface.

Interfacial dynamic properties and dilational rheology of mixed anionic and cationic Gemini surfactant systems at air–water interface

The interfacial dynamic properties and dilational rheology of sulfonate Gemini surfactant (SGS-12), two bisquaternary ammonium dibromides with different carbon chain lengths (BQAS-12, 16), and two mixed anionic and cationic Gemini surfactant solutions (SGS-12/BQAS-12 and SGS-12/BQAS-16) air–water interface were investigated using the drop shape analysis. Results indicate that the adsorption mechanism of surfactants is diffusion-controlled at dilute concentrations, whereas the adsorption process gradually shifts to a mixed kinetic-diffusion control with increasing the surfactant concentration. The surface tension of the mixtures reaches the minimum value when the molar ratios of SGS-12/BQAS-12 and SGS-12/BQAS-16 mixtures are 6:5 and 8:5, respectively. The effects of oscillating frequency and concentration on the dilational properties were also examined. As the dilational frequency increases, the dilational modulus of these surfactants increases gradually, but the phase angle decreases. The dilational elasticity peaks at a certain concentration, which is less than the critical micelle concentration. Moreover, the effects of SGS-12 concentration on the dilational interfacial rheology of the BQAS-12/SGS-12 and BQAS-16/SGS-12 mixtures were studied. The surface activities of these mixtures show positive correlation with the phase angle. Moreover, the surface film mainly exhibits viscosity as the surface tension reaches the minimum.

Interactions of Divalent and Trivalent Metal Counterions with Anionic Sulfonate Gemini Surfactant and Induced Aggregate Transitions in Aqueous Solution.

Interactions of multivalent metal counterions with anionic sulfonate gemini surfactant 1,3-bis(N-dodecyl-N-propanesulfonate sodium)-propane (C12C3C12(SO3)2) and the induced aggregate transitions in aqueous solution have been studied. Divalent metal ions Ca(2+), Mg(2+), Cu(2+), Zn(2+), Mn(2+), Co(2+), and Ni(2+) and trivalent metal ions Al(3+), Fe(3+), and Cr(3+) were chosen. The results indicate that the critical micelle concentration (CMC) of C12C3C12(SO3)2 is greatly reduced by the ions, and the aggregate morphologies of C12C3C12(SO3)2 are adjusted by changing the nature and molar ratio of the metal ions. These metal ions can be classified into four groups because the ions in each group have very similar interaction mechanisms with C12C3C12(SO3)2: (I) Cu(2+) and Zn(2+); (II) Ca(2+), Mn(2+) and Mg(2+); (III) Ni(2+) and Co(2+); and (IV) Cr(3+), Al(3+) and Fe(3+). Cu(2+), Mg(2+), Ni(2+), and Al(3+) then were selected as representatives for each group to further study their interaction with C12C3C12(SO3)2. C12C3C12(SO3)2 interacts with the multivalent metal ions by electrostatic interaction and coordination interaction. C12C3C12(SO3)2 forms prolate micelles and plate-like micelles with Cu(2+), vesicles and wormlike micelles with Al(3+) or Ni(2+), and viscous three-dimensional network structure with Mg(2+). Moreover, precipitation does not take place in aqueous solution even at a high ion/surfactant ratio. The related mechanisms have been discussed. The present work provides guidance on how to apply the anionic surfactant into the solutions containing the multivalent metal ions, and those aggregates may have potential usage in separating heavy metal ions from aqueous solutions.

Aggregation behavior of anionic sulfonate gemini surfactants with dodecylphenyl tails

Abstract A series of anionic sulfonate gemini surfactants with the general structure [(C12H25)(C6H3SO3−)O(CH2)mO(C6H3SO3−)(C12H25)]2Na+, designed as S, where m = 2, 4, 6 and 8 denotes the number of carbon atoms in the oligomethylene spacer, was synthesized, and the surfactants’ physicochemical properties and aggregation behavior were characterized. Compared with their single-tail analog, the gemini surfactants were observed to be more effective in decreasing the surface tension and their critical micelle concentrations (CMC) were at least two orders of magnitude lower. The aggregation process of the gemini surfactants in aqueous solution was investigated by dynamic light scattering (DLS). The formation of multivesicular structures consisting of several small vesicles surrounded by vesicular membrane was observed by cryogenic transmission electron microscopy (cryo-TEM).

Synthesis and Performance of Novel Sulfonate Gemini Surfactant with Trialkyl Chains

A new type of sulfonate gemini surfactant with three lipophilic alkyl chains (3C10-DS) was synthesized, and the structure of the product was confirmed by using the infrared spectrum and mass spectrum. Its critical micelle concentration (CMC) is 0.41 mmol/L, one order of magnitude lower than those of convectional (single-chain) surfactants, and the minimum surface tension is 27.6 mN/m. The interfacial tension (IFT) between the compound system of 3C10-DS and petroleum sulfonate (PS) and the simulated oil reaches ultra-low levels (10−3 mN/m), and there exists significant synergistic effect between 3C10-DS and PS. The compound flooding system consisting of polymer and the mixture of 3C10-DS and PS can effectively improve oil recovery for high-medium permeability cores and have a good application prospect in enhancing oil recovery.

Synthesis of New Salt‐Resistant Sulfonate Gemini Surfactants with Hydroxyl Groups

AbstractThough the gemini surfactants have unique properties, their high cost limits their scope of application. The new salt‐resistant sulfonate gemini surfactants disodium 5,12‐bis(alkyloxymethyl)‐4,7,10,13‐tetraoxa‐2,15‐dihydroxyhexadecane 1,16‐disulfonates bearing two alkyl chains, two hydroxyl and two sulfonate groups were prepared from fatty alcohol, epichlorohydrin, glycol, sodium hydroxide, sodium bisulfite and sodium sulfite. Their synthesis exhibited the advantages of low raw material cost, mild reaction conditions and easy operation. The structures of prepared compounds were confirmed by FTIR and 1H NMR. These gemini surfactants show excellent surface‐active properties, good salt resistance and excellent foaming ability.

Micellization of anionic gemini surfactants and their interaction with polyacrylamide

A series of anionic gemini surfactants have been synthesized. The surface properties and micellization process of as-prepared sulfonate gemini surfactants (SGS) and carboxylate gemini surfactant (CGS) have been studied by surface tension measurement and isothermal titration microcalorimetry. Meanwhile, the interaction of these five surfactants with polyacrylamide (PAM) was investigated using surface tension, steady-state fluorescence measurement, and isothermal titration microcalorimetry. The results show that the critical micelle concentrations (CMCs) of above-mentioned surfactants are more than 1 order of magnitude lower than those of corresponding single chain surfactants. Moreover, the enthalpy of micelle formation (ΔH mic) for the investigated gemini surfactants is negative. In the surfactant–PAM systems, the thermodynamic parameters of binding have also been determined. The conclusion may be drawn that the binding strength of SGS onto PAM is stronger than that of CGS, resulting from more compact structure of SGS aggregates. With increasing surfactant hydrophobicity, the values of ΔH agg become more exothermic and a ΔS agg decrease was observed. Therefore, the interaction between SGS and PAM is enthalpy-driven.

Synthesis and Properties of Novel Cashew-Based Sulfonate Gemini Surfactant

A novel cashew-based gemini surfactant was synthesized from cashew phenol, 1, 3-dibromopropane and chlorosulfonic acid through etherification, sulfonation and neutralization. The critical micelle concentration (cmc) for cashew-based gemini surfactant was 6.2×10-2 mmol·L-1, the surface tension (γcmc) was 36.92 mN.m-1. Foam properties and emulsification properties were investigated including the affection of inorganic salts and sodium hydroxide. The oil / water interfacial tension can be decreased efficiently to 10-3mN / m.

A New Anionic Oxalamide Lauryl Succinate Sodium Sulfonate Gemini Surfactant: Microwave‐Assisted Synthesis and Surface Activities

AbstractAn anionic Gemini surfactant, oxalamide lauryl succinate sodium sulfonate, was synthesized successfully through amidation, esterification and sulfonation reactions under microwave irradiation conditions by using maleic anhydride, ethylenediamine, lauryl alcohol, sodium sulfite as the starting materials. The best reaction conditions for synthesize the target product were obtained by single factor and orthogonal optimization methods. FTIR, elemental analysis and 1H‐NMR analysis were used to confirm the chemical structure of the surfactant. The critical micelle concentration (CMC) in aqueous solution, surface tension, emulsification capacity and foaming power were determined. The critical micelle concentration and γCMC are respectively equal to 3.5 × 10−4 mol L−1 and 21.5 mN m−1. It was found that microwave‐assisted synthesis is an efficient means of preparation of this anionic Gemini surfactant with shorter times and higher yields.

Influence of Three Anionic Gemini Surfactants with Different Chain Lengths on the Optical Properties of a Cationic Polyfluorene

The effects of three sulfonate gemini surfactants with different hydrophobic chain lengths (8, 10, and 12 carbon atoms) on the optical properties of a fluorene-based conjugated cationic polymer poly{[9,9-bis(6'-N,N,N-trimethylammonium)hexyl]-fluorene-phenylene} bromide (PFP) dissolved in DMSO-water solutions (4% v/v) or water were investigated, respectively. When surfactants with PFP dissolved in DMSO-water solutions (4% v/v) are incubated, a decrease in photoluminescence (PL) intensity and a red shift of emission maxima are obtained at low surfactant concentrations. Intriguingly, two different Stern-Volmer constants (KSV1 and KSV2) are obtained and analyzed in detail for the first time. Further increase in the surfactant concentration enhanced PL intensity, and distinct blue shifts of both absorption and emission maxima are observed. Importantly, the turning point between the emission quenching and enhancement is closely related to the hydrophobic chain length: the longer the chain length, the earlier the turning point appears. Simulation studies provide strong evidence to explain these phenomena. Surface tension measurements show more insight on the interactions between PFP and surfactant. On the contrary, no emission quenching is obtained at low surfactant concentrations for PFP dissolved in water.

Synthesis of Cardanol Sulfonate Gemini Surfactant and Enthalpy-Entropy Compensation of Micellization in Aqueous Solutions

A novel cardanol sulfonate Gemini surfactant with high surface properties was synthesized by cashew phenol, 1,3-dibromopropane and chlorosulfonic acid through three steps procedure of etherification, sulfonation and neutralization. A surface tension method was employed to investigate the thermo-dynamic properties of micellization in aqueous solution for cardanol sulfonate Gemini surfactant synthesized in laboratory. As a result, the micellization of cardanol sulfonate Gemini surfactant in aqueous solutions is spontaneous and entropy-driven. The micellization process is enthalpy-entropy compensated with the compensation temperature (Tc) of 308 ± 1 K.

Interaction of Anionic Sulfonate Gemini Surfactant with PEO-PPO-PEO Triblock Copolymers

Interaction of Anionic Sulfonate Gemini Surfactant with PEO-PPO-PEO Triblock Copolymers

Synthesis and Performance of a Multi‐Purpose Gemini Precursor and the Derivative Alkylaryl Sulfonate Gemini Surfactants

AbstractThe phenol–formaldehyde condensation reaction to synthesize a gemini precursor was renewed by using high efficient and environmentally benign resin catalysts instead of protonic acids, and the conversion, yield and selectivity of the reaction were all upgraded from the 60 % by the traditional way to over 90 % by the new way. Three alkylaryl sulfonate gemini surfactants were derived from the above gemini precursor by O‐methylation, sulfonation and neutralization, that is, sodium salt of sulfonated bis(2‐hydroxy‐5‐nonylphenyl)methane (SBHNM), sodium salt of sulfonated bis(2‐hydroxy‐5‐dodecylphenyl)methane (SBHDM) and sodium salt of sulfonated bis(2‐methoxy‐5‐nonylphenyl)methane (SBMNM). And their performances in aqueous solution were further investigated. The results show that the three gemini surfactants exhibit higher effectiveness and efficiency in surface tension reduction than a monomeric reference surfactant sodium dodecylbenzene sulfonate (SDBS). Furthermore their critical micelle concentration values are at least one order of magnitude lower than that of SDBS. It is also shown that O‐methylation of the hydroxyl group in the gemini precursor is effective at improving the surface activity of the gemini surfactants, such as efficiency in surface tension reduction, foam stability and calcium stability. It is suggested that the synthesized hydrophobic skeleton could be a multi‐purpose gemini precursor from which various gemini surfactants could be derived by further hydrophobic or hydrophilic modification.

Aggregate Transitions in Mixtures of Anionic Sulfonate Gemini Surfactant with Cationic Ammonium Single-Chain Surfactant

Aggregation behaviors in mixtures of an anionic gemini surfactant 1,3-bis(N-dodecyl-N-propanesulfonate sodium)-propane (C(12)C(3)C(12)(SO(3))(2)) and a cationic single-chain surfactant cetyltrimethylammonium bromide (CTAB) have been investigated in aqueous solutions at pH 9.5 by turbidity, rheology, isothermal titration microcalorimetry (ITC), cryogenic transmission electron microscopy, and dynamic light scattering. Reversible aggregate transitions from spherical micelles to wormlike micelles, vesicles, and back to wormlike micelles and spherical micelles are successfully realized through fine regulation over the mixing ratio of surfactants, i.e., the anionic/cationic charge ratio. The five aggregate regions display distinguished phase boundaries so that the aggregate regions can be well controlled. From thermodynamic aspect, the ITC curves clearly reflect all the aggregate transitions and the related interaction mechanism. The self-assembling ability of the C(12)C(3)C(12)(SO(3))(2)/CTAB mixtures are significantly improved compared with both individual surfactants. Micelle growth from spherical to long wormlike micelles takes place at a relative low total concentration, i.e., 2.0 mM. The wormlike micelle solution at 10 mM or higher shows high viscosity and shear thinning property. Moreover, the C(12)C(3)C(12)(SO(3))(2)/CTAB mixtures do not precipitate even at 1:1 charge ratio and relative high concentration. It suggests that applying gemini surfactant should be an effective approach to improve the solubility of anionic/cationic surfactant mixtures and in turn may promote applications of the surfactant mixtures.

Synthesis and Properties of a Novel Linear Alkylated Diphenylmethane Sulfonate Gemini Surfactant

AbstractThe linear alkylated diphenylmethane sulfonate (C12‐DSDM) was synthesized by a four‐step reaction with lauric acid, diphenylmethane and chlorosulfonic acid as raw materials. The structure of the final product was characterized by MS. The air–liquid surface tensions at various temperatures and salt solutions (NaCl) were measured by using the drop‐volume technique and the thermodynamic parameters of the micellization were calculated. The results show that the critical micelle concentration (CMC) and γCMC of the surfactant are 1.452 mmol L−1 and 38.49 mN m−1 at 298 K. With an increase in temperature, the CMC gradually increases, the γCMC and the maximum surface adsorption capacity Γmax decrease. The free energy of micelle formation is negative (−51.2 to −60.5 kJ mol−1).

Effects of calcium ions on solubility and aggregation behavior of an anionic sulfonate gemini surfactant in aqueous solutions

Effects of calcium ions on the solubility and aggregation behavior of an anionic sulfonate gemini surfactant 1,3-bis(N-dodecyl-N-propylsulfonate sodium)-propane (12-3-12(SO3)2) have been studied in aqueous solution. Compared with single-chain surfactant sodium dodecylsulfate, 12-3-12(SO3)2 shows much better performance to the hardness tolerance with calcium ions. Moreover aggregates of the Ca2+/12-3-12(SO3)2 complexes in clear solutions influence the morphologies of the precipitates. At 12-3-12(SO3)2 concentrations lower than 1.5mM, the small spherical micelles of Ca2+/12-3-12(SO3)2 in clear solutions generate precipitates of solid particles owing to complexation of surfactant monomers with Ca2+. At 12-3-12(SO3)2 concentrations higher than 1.5mM, the Ca2+/12-3-12(SO3)2 complexes transform into large compact spherical aggregates and then into long wormlike micelles. These large aggregates are well dispersed in aqueous solutions and efficiently complex calcium ions. In particular, long wormlike micelles are entangled with each other at 100.0mM CaCl2 and 100.0mM 12-3-12(SO3)2 exhibiting viscoelastic properties. In addition, the stacking of long wormlike micelles produces precipitates with ordered fibrillar structures. This work reveals that such anionic sulfonate gemini surfactants are better candidates than single-chain surfactants in applications with high hardness levels, and the ordered aggregate structures may have potential applications in materials science.

Synthesis and Surface Active Properties of a Novel Linear Dodecyl Diphenyl Ether Sulfonate Gemini Surfactant

AbstractThe linear dodecyl diphenyl ether sulfonate gemini surfactant (C12‐DLADS) has been synthesized by a new route from lauric acid according to a five‐step reaction sequence consisting of acidification, Friedel–Crafts acylation, Clemmensen reduction, sulfonation and a neutralization reaction. The surfactant and intermediates were characterized by 1H‐NMR, HPLC/MS and elemental analysis. The properties have been studied by surface tension (γCMC) and conductivity measurements. The thermodynamic parameters of micellization were calculated. The test results show that C12‐DLADS has lower critical micelle concentration (CMC) and better capability for lowering the γCMC. The γCMC and CMC are 36.04 mN/m and 6.03 × 10−4 mol/L respectively at 45 °C. Moreover, with the increase in temperature, the conductivity of C12‐DLADS increased, while the counterion binding K0 decreased. The thermodynamic data show that the micellization process for the surfactant C12‐DLADS is entropy driven.

Study on Aggregation Behaviour of Mixture of Alkylbenzene Sulfonate Gemini Surfactant Ib and Nonionic Surfactant Triton X-100

The interaction between the anionic Gemini surfactant Ib and the conventional nonionic surfactant Triton X-100 was investigated. The critical micelle concentrations (cmc) of different mixtures were measured by surface tension measurement at 298 K. The results showed that the cmc of different mixtures at any mole ratio was lower than that of either pure Ib or Triton X-100, indicating synergetic behavior. And the interaction parameter ß values for the mixed micelles were negative, showing attractive interaction between these surfactant molecules. Besides, the micelle aggregation number (N) was measured using a steady state fluorescence quenching method. The N values of the mixed surfactant system were larger than that of pure Ib but lower than pure Triton X-100 at any ratio.

Synthesis of Three Novel Anionic Gemini Surfactants and Comparative Studies of Their Assemble Behavior in the Presence of Bovine Serum Albumin

Three novel anionic sulfonate gemini surfactants, sodium 4,4'-(10,19-dioxo-9,11,18,20-tetraazaoctacosane-9,20-diyl) dibenzenesulfonate (Surfactant I), sodium 4,4'-(12,21-dioxo-11,13,20,22-tetraazadotriacontane-11,22-diyl) dibenzenesulfonate (Surfactant II), and sodium 4,4'-(14,23-dioxo-13,15,22,24-tetraazahezatriacontane-13,24-diyl) dibenzenesulfonate (Surfactant III), with different lengths of hydrophobic tail have been synthesized, and their assembly behavior in the presence of bovine serum albumin (BSA) has been studied using spectral methods and molecular modeling methods at physiological pH and 298 K. Critical micelle concentrations (CMCs) of the three surfactants have been determined by surface tension measurements. Despite the obvious decrease of CMC with the increase of tail length, fluorescence spectra have shown much closer CAC in the presence of BSA. Surfactant II shows the highest CAC of 3.19 × 10(-5) mol L(-1) compared with the other two. The polarity of the microenvironment in BSA-surfactant systems has been investigated using pyrene as the probe. In addition, far-UV CD spectra studied the change of the secondary structure content of BSA caused by the three surfactants. The features of the assembly behavior were discussed by three concentration regions. Surfactant II could unfold the protein much more efficiently than the other two surfactants at low concentration, but at high concentration, the change of the secondary structure and the formation of hydrophobic microenvironment show a direct relationship to the length of the hydrophobic tail with the increase of the surfactant concentration.

Synthesis and Properties of X‐Type Alkyl Sulfonate Gemini Surfactants Derived from Cyanuric Chloride

AbstractA series of X‐type alkyl sulfonate Gemini surfactants (XCn, n = 6, 8, 10) was synthesized by a simple method. The chemical structures of the prepared compounds were confirmed by 1H NMR, 13C NMR, ESI–MS and Elementary analysis. The surface activity and thermodynamic properties of micellization of the X‐type alkyl sulfonate Gemini surfactants were compared with sodium dodecylsulfate by means of surface tension. The properties of XCn are superior to those of SDS such as the γCMC and CMC of XC10 are 26.3 mN/m and 0.2 mmol/L respectively. The adsorption isotherms for XCn were established by fitting the pre‐CMC surface tension data with a quadratic function. The thermodynamic parameters of micellization (, , ) derived from electrical conductivity indicate that the micellization of XCn is entropy‐driven.