Influence of Hydrocarbon Chain Branching on Foam Properties of Olefin Sulfonate with FoamScan

The influence of surfactant structure on foam properties of internal olefin sulfonate (IOS) and alpha olefin sulfonate (AOS) in aqueous solutions was estimated from measurements of the foamability, foam stability, and foam morphology, as obtained from conductivity and image analyses techniques. It was found that the foamability and foam stability of C_16–18 AOS are higher compared to that of C_16–18 IOS, indicating that hydrocarbon chain branching decreases the foamability and foam stability. The foamability and foam stability are enhanced with increasing surfactant concentration, which increases the adsorbed quantity of surfactant molecules at the air–water interface. The influence of hydrocarbon chain branching on foam morphology was also investigated. It was found that foam cells produced by branched chain C_16–18 IOS are larger than the foam cells generated by straight chain C_16–18 AOS.     

Surface Dilational Rheology,Foam, and Core Flow Properties of Alpha Olefin Sulfonate

The surface tension, surface dilational rheology, foaming and displacement flow properties of alpha olefin sulfonate (AOS) with inorganic salts were studied. The foam composite index (FCI), which reflects foaming capacity and foam stability, is used to evaluate foam properties. It is found that sodium and calcium salts can lead to decreases in AOS surface tension, critical micelle concentration, and molecular area at the gas–liquid interface. Sodium ions reduce the surface dilational viscoelasticity (E) and FCI of AOS, while calcium ions can enhance the E of AOS and make the FCI of AOS reach a maximum. In the solution containing calcium and sodium ions, the FCI of AOS is improved. Crude oil reduces the FCI of AOS. Injection pressure and displacing efficiency of AOS alternating carbon dioxide (CO₂) injection are higher than injections of water alternating with CO₂ or CO₂ alone in low permeability cores.     

Synthesis and Characterization of Novel Aryl Alkyl Sulfonates Based on Nonylphenol

A series of nonylphenol-substituted alkyl sulfonates (C _x NPAS, x = 8, 10, 12, 14, 16) with two hydrocarbon chains and two different hydrophilic groups has been synthesized from α-olefins and nonylphenol. The respective products have a “pseudo-gemini” surfactant structure. The structures of the C _x NPAS have been characterized by IR, UV, ¹H nuclear magnetic resonance, electrospray ionization mass spectrometry, and elemental analysis. The effects of carbon chain length of the obtained surfactants on properties such as the critical micelle concentrations (CMC) in aqueous solutions, surface tension at the CMC (γ _CMC), and efficiency of adsorption at the water/air interface (pC ₂₀) have been determined. The γ _CMC of the surfactants first decreased and then increased with increasing length of the carbon chain x, and reached a minimum of 29.25 mN/m at x = 10, which is much lower than that of α-olefin sulfonate (AOS) (33.52 mN/m). The CMC decreased and pC ₂₀ increased with increasing x. The introduction of the hydroxyl group is responsible for multiple molecular conformations at the water/air interface and leads to a greater molecular area A _min and smaller Γ_max than those of AOS.     

Safety of Alpha Olefin Sulfonates

Alpha olefin sulfonates (AOS) belong to the anionic surfac-tant class. They are efficient, readily biodegradable cleaning agents. This paper reviews the safety aspects of AOS, in-cluding acute toxicity, teratogenicity, animal sensitization, human sensitization, chronic toxicity and lifetime studies -cancer bioassay. Prensented at the 56th Annual Meeting of The Soap and Detergent Association, Jan, 27–30, 1983, Boca Raton, Florida.     

烯基磺酸盐的开发,生产,性能及其应用

本文综述了α－烯基磺酸盐的开发,生产过程,产品性能及其在家用洗涤剂中的应用。     

Photosulfochlorination Synthesis and Physicochemical Properties of Methyl Ester Sulfonates Derived from Lauric and Myristic Acids

The photosulfochlorination process has been used in earlier works to produce n-alkane sulfonates. In this work, this process was applied for the first time on lauric and myristic fatty acids, leading to methyl ester sulfonates (MESs). The operating conditions were optimized and the isolation method described. Apart from the known advantages of this reaction, namely the use of sulfuryl chloride, the visible light and short reaction time, this process led to a clear mono-sulfonate products and thus allowed avoiding the bleaching step. The chemical composition of these surfactants was determined and their structures characterized by Fourier transform infrared spectroscopy, liquid chromatography-electrospray ionization tandem mass spectrometry and proton nuclear magnetic resonance. The physicochemical properties of these surfactants such as surface tension, critical micelle concentration, maximum surface excess and minimum area per molecule of surfactant at the air/water interface were determined. The Krafft point was determined experimentally and compared to the MES literature data. The experimental and calculated hydrophilic–lipophilic balance values obtained compared well. The foaming power using Bartsch’s method was presented and the results obtained compared to those of similar structures and those of sodium dodecyl sulfate.     

Use of high-active alpha olefin sulfonates in laundry powders

Alpha olefin sulfonates (AOS) have been used successfully for many years in laundry and personal-care products throughout Asia. Among their documented positive attributes are good cleaning and high foaming in both soft and hard water, rapid biodegradability, and good skin mildness. AOS has commonly been marketed as approximately 40%-active aqueous solutions. However, with the increased importance of compact powder detergents produced by processes other than spray drying, high-active forms of AOS including 70%-active pastes and 90+%-active powders are now being utilized for that product sector. In this regard, the rheological properties of non-Newtonian AOS and AOS/additive pastes at relevant process temperatures were measured and found potentially suitable for agglomeration processes. Also, the relationship of AOS powder particle size to surfactant solubility at various wash conditions was examined to allow determination of the optimal size for both detergency and processing of laundry powders. Both paste rheology and powder morphology are critical factors for the successful use of high-active AOS in compact powder detergents.     

Relationship of structure to properties of surfactants. 16. Linear decyldiphenylether sulfonates

The properties of some well-characterized sodium linear decyldiphenylether (C₁₀DPE)sulfonates have been studied. Among the properties investigated are dynamic and equilibrium surface tension, critical micelle concentration (CMC), area per molecule at the aqueous solution/air interface, wetting time by the Draves technique, foaming by the Ross-Miles method, solubilization, and hydrotropy. The decyldiphenylether moiety appears to be equivalent to a terminally substituted straight alkyl chain of 16 carbon atoms. The trialkyl- and dialkyl-mono-sulfonates have solubilities of < 0.01 g/dm³ in water, but are readily soluble in hexane. The didecyldiphenyl ether disulfonate (DADS) has a very low CMC value (1.0 × 10⁻⁵ mol dm⁻³) in aqueous 0.1 N Na⁺ solution (NaCl), characteristic of surfactants with two hydrophilic and two hydrophobic groups. It also has a much larger area per molecule at the aqueous solution/air interface than the monodecyldiphenyl-ether monosulfonate (MAMS) and a much higher surface tension at the CMC. MAMS has a much lower surface tension at a surface age of 1 second (γ_1s) than either DADS or the monodecyldiphenylether disulfonate (MADS). In agreement with γ_1s and γ_eq values, wetting times increase in the order: MAMS < DADS < MADS and initial foam heights decrease in the order: MAMS > DADS > MADS. Solubilization for three water-insoluble surfactants decreases in the order: DADS > MAMS > MADS, while hydrotropy is most pronounced with the disulfonates.     

内烯烃磺酸盐表面活性剂的合成与性能

以内烯烃为原料,以三氧化硫·二氧六环络合物为磺化试剂进行磺化反应,制得内烯基磺酸,经中和反应制得内烯烃磺酸盐表面活性剂;采用红外光谱对产物的结构进行了表征,结果表明产物结构与预期产物结构相符。考察了所合成的内烯烃磺酸盐表面活性剂的起泡性能和乳化性能,内烯烃磺酸盐具有良好的起泡性能和稳泡性能,以及优良的乳化性能和乳化稳定性;采用TX500界面张力对产物的界面张力进行了测定,表明所合成的新型内烯烃磺酸盐能够显著降低原油的界面张力最低降至(0.000 7 mN/m),具有很高的界面活性。     

Effect of branched PP content on the physical properties and cell growth during foaming of TPOs

Linear/branched PP blends at various ratios were used as the matrix for thermoplastic olefin (TPO) compounds, containing an ethylene–octene copolymer dispersed phase. A detailed investigation of the physical properties of these blends revealed that addition of branched PP (BPP) resulted in improved stiffness and flexural properties. Given that the phase morphology of the blends and the interfacial tension between their components remained virtually unaffected, these improvements are attributed to the higher stiffness of the BPP‐containing matrices. Talc‐filled TPOs containing branched PPs exhibited further improvements in the stiffness and flexural properties. An investigation into the bubble growth process during foaming using a batch foaming simulation system revealed that the presence of BPP resulted in a slight delay in cell nucleation, whereas the rate of bubble growth was not significantly altered. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Interfacial activity of narrow-range alcohol oxyethylates

Surface and interfacial tension isotherms for narrow-range distribution ALFOL 1214 alcohol oxyethylates were determined and compared with those obtained for broad-range alcohol oxyethylates. Various adsorption parameters were estimated. The effectiveness of surface tension reduction decreases when the length of polyoxyethylene hydrophile increases. Micellization is observed at log cmc ranging from −4.7 to −3.3. Effects of the length and distribution of the polyoxyethylene chain on cmc are very small. A minimum of A _min/N _av ^0.5 is obtained for N _av=8, where A _min and N _av denote the minimum interfacial area occupied by a statistical molecule at the saturated interface and the average degree of oxyethylation, respectively. The interface becomes saturated at pC ₂₀=−5.61±0.35, where pC ₂₀ denotes the logarithm of concentration required to obtain the surface pressure equal to 20 mNm⁻¹. The highest and lowest values of the surface excess at saturation and the free energy of adsorption, respectively, are obtained for an average degree of oxyethylation equal to 8. Parameters are correlated with the average degree of oxyethylation and the oxyethylene chain distribution parameter according to empirical second-order polynomials. Small differences in adsorption abilities at the water/air interface are only observed for narrow- and broad-range distributed oxyethylates. The differences become important for adsorption at the hexadecane/water interface. The lowest values of interfacial tension are obtained for narrow-range oxyethylates with N _av=7 and 8. The Krefeld fabric detergency tests indicated that the best detergency was observed for alcohol oxyethylates with N _av=5–7. Narrow-range oxyethylates exhibit somewhat better washing abilities than the broad-range products. No relationship between detergency of alcohol oxyethylates and their abilities to adsorb at the water/air and water/hydrocarbon interfaces is observed.     

Surface activity of mixtures of narrow-range distributed alcohol oxyethylates and sodium dodecylbenzenesulfonate

Surface and interfacial tension, emulsion inversion temperature, and detergency were determined for mixtures of sodium dodecylbenzenesulfonate and narrow-range distributed alcohol C₁₂−C₁₄ oxyethylates of different hydrophilicity. The mixtures of ionic and nonionic surfactants behave similarly to nonionic and ionic surfactants at the air/water and hydrocarbon/water interfaces, respectively. The air/water interface is mainly occupied by nonionic surfactant molecules. However, the interfacial tensions for mixtures of nonionic and ionic surfactants are similar to those of sodium dodecylbenzenesulfonate. Mixtures of narrow-range distributed oxyethylates and sodium dodecylbenzenesulfonate have a higher detergency at 40°C than individual components.     

Gemini Cationic Surfactants: Synthesis and Influence of Chemical Structure on the Surface Activity

Three cationic gemini surfactants were synthesized and characterized using different methods. Their surface activities were measured using surface and interfacial tension measurements. The effect of the spacer chain length on the surface activity, emulsification power and interfacial tension was studied. The thermodynamic parameters showed the tendency towards micellization and adsorption. The results showed that longer spacers increased the micellization tendencies of the surfactants, while shorter spacers increased the adsorption tendency at the air–water interface.     

长链烷基苯磺酸钠Gemini表面活性剂的合成和表面活性

以脂肪酸、苯酚、乙二醇为原料,经酰化反应、酯化反应、Fries重排、氢化还原反应、磺化以及中和反应等步骤,合成出3种长链烷基苯磺酸钠Gem in i表面活性剂。用IR、1HNMR和ESI-MS对产物进行了结构鉴定。以W ilhelmy-p late法测定了30℃时它们在水溶液中的临界胶束浓度(CMC)和临界胶束浓度下的表面张力(γCMC)。纯水溶液中其临界胶束浓度(CMC)为10-4~10-5mol/L,γCMC为35~37 mN/m;随着苯环上长链烷基碳数(n=8、10、12)的增加,CMC分别为5.94×10-4、1.53×10-5、0.46×10-5mol/L;γCMC分别为36.9、34.4、34.4 mN/m。结果表明,此类表面活性剂具有比较好的表面活性。     

直链烷基萘磺酸钠的合成及界面活性研究

为研究直链烷基萘磺酸盐结构与界面性能的关系,以α-溴化萘为原料,经交叉耦合反应、磺化反应、中和反应等步骤,合成了5种结构明确的直链烷基萘磺酸钠,烷基链的碳数分别为6、8、10、12、14,产物收率50%～60%。用高效液相色谱、质谱、核磁共振氢谱对其进行了色谱纯度、相对分子质量及结构表征,产物色谱纯度均高于96.0%。测量了各烷基萘磺酸钠的NaCl水溶液与正壬烷的界面张力,证实了临界胶束浓度随烷基碳链的增长而减小。     

Surface activity of mixtures of oxyethylated methyl dodecanoate and sodium dodecylbenzenesulfonate

Surface and interfacial tension and detergency of mixtures containing oxyethylated methyl dodecanoate and sodium dodecylbenzenesulfonate were determined. Synergism in the surface tension reduction was not observed. The competition for adsorption at the air/water interface between oxyethylated methyl dodecanoate and sodium dodecylbenzenesulfonate depended on the considered surface tension, the weight ratio of surfactants in the aqueous phase, and the hydrophile-lipophile balance of the nonionic surfactant. Generally, coverage of the interface with oxyethylated methyl dodecanoate increased when surface tension decreased. Nonionics were the dominant species at the interface in the important region of surface activity, i.e., for surface tensions below 40 mN m⁻¹. The mole fraction of the hydrophobic nonionic at the interface was higher than the contribution of hydrophilic oxyethylates. An increase of the surfactant ratio in the bulk phase affects the interfacial ratio of surfactants in the same way. The lowest interfacial tension (1.5 mN m⁻¹) at the hexadecane/water interface was observed for oxyethylated methyl dodecanoate having an average degree of oxyethylation equal to 8 and 10. Nearly 5 min was needed to achieve equilibrium value. Mixtures with sodium dodecylbenzenesulfonate decreased the interfacial tension somewhat less efficiently but the equilibrium was rapidly established. The standard washing powders containing oxyethylated methyl dodecanoates exhibited washing ability similar to that obtained for the powder with traditional alcohol oxyethylate.     

High pressure liquid chromatography of alpha olefin sulfonates

Alpha olefin sulfonates (AOS) are a complex mixture of the posi-tional isomers of hydroxyalkane sulfonates, alkene sulfonates, and disulfonates. This paper describes a qualitative method for separat-ing these various components by reverse-phase high pressure liquid chromatography. The column utilized was a DuPont Zorbax TMS (4.6 mm × 25 cm) with a water/methanol (25:75, v/v) mobile phase containing sodium nitrate at a concentration of 0.4M. The hydroxyalkane sulfonate and alkene sulfonate peaks were identified using laboratory prepared standards. The disulfonate peaks were located using controlled sulfonation conditions. More work needs to be done to separate an overlap of C₁₆ 3-hydroxyalkane sulfonate and C₁₄ 2-alkene sulfonate in 1416 AOS. However, if studies are based on single carbon number AOS samples, the overlap of these peaks can be avoided. This method can be utilized as a qualitative tool for the comparison of sulfonation runs, the identification of AOS within a detergent, or the identfication of the olefin type used for sulfonation.     

Thermodynamic Parameters and Interfacial Properties of Poly(ethylene glycol)-octyl Sulfosuccinates

Surface tension of a series of poly(ethylene glycol)-octyl sulfosuccinates at different temperatures was measured, and the interfacial properties were investigated in the absence and presence of inorganic salts. Surface tension results indicate that critical micelle concentration (CMC) values of five surfactants (C8-PEG200, C8-PEG400, C8-PEG600, C8-PEG800, and C8-PEG1000) decrease as the molecular weight of polyethylene glycol (PEG) segments and the experimental temperature increases. The surface activity of the C8-PEG series changes with temperature, and the surface tension at the CMC (γ_CMC) of the C8-PEG series decreases initially and then increases as the PEG molecular weight increases. This behavior may be attributed to the dehydration of the surfactant molecules, resulting in the change of hydrophile–lipophile balance for the different EO numbers in the surfactant molecules, which form a different surface energy film at the air–water interface. Negative ΔG_m indicates that the micellization process of these surfactants is spontaneous and an entropically driven process. For the water/alkane interface, these surfactants have low interfacial activity. The interfacial tension (IFT) between these surfactants and alkanes increases first and then decreases with the increase in the molecular weight of PEG segments. After the addition of salt, the interfacial activity of the investigated surfactants increases significantly. The IFT between C8-PEG800 and 10–12 alkanes and between C8-PEG1000 and 12–16 alkanes reaches a low IFT magnitude of 10⁻² mN m⁻¹ in the presence of 0.5% CaCl₂ or the mixed inorganic salts 0.5% NaCl+0.5% CaCl₂.     

The Adsorption of Hydroxyl Mixed Ether Nonionic Polymeric Surfactants at Air/Water and Solid/Water Interfaces: Influence of Surfactant Molecular Structure

This paper reports the adsorption of four nonionic Hydroxyl Mixed Ether (HME) polymeric surfactants at air/water and solid/water interfaces. The characteristics of these nonionic surfactants, including surface tension, critical micelle concentration (CMC) and adsorption onto saponite and Teflon are investigated. At the air/water interface, the surface activity of the HME-surfactants decreases with an increasing degree of ethoxylation. The surface tension results indicate that CMC, surface tension at CMC (γ_CMC), and the minimum surface area per adsorbed HME-surfactant molecule (A _min) all increased with the degree of ethoxylation for surfactants with similar hydrocarbon chain lengths. Additionally, a strong adsorption onto the saponite (synthetic clay) was measured and found dependent on both the degree of ethoxylation and the hydrocarbon chain length. This adsorption was also observed by atomic force microscopy (AFM). On the other hand, the adsorption of HME-surfactants on Teflon was independent of the hydrocarbon chain length.     

Comparative Study of Effect of Surfactant-Polymer Interactions on Properties of Alkyl Polyglucosides and Alpha Olefin Sulphonate

The properties of Alpha Olefin Sulphonate (AOS) and Alkyl polyglucosides (APG) were studied in the presence and absence of nonionic polymers such as polyethylene glycol, poly vinyl pyrrolidone and methyl cellulose and hydroxy propyl cellulose. Properties like surface tension, foaming, viscosity and emulsification were studied at a constant concentration of polymer (0.1%) and varying concentrations of surfactant. It was found that at low surfactant concentrations there is an association between surfactant and polymer at the liquid/air surface in the case of an anionic surfactant and a nonionic polymer, which is not seen in the case of nonionic surfactants and nonionic polymers. A nonionic polymer reduces the surface tension of AOS by forming a surfactant-polymer complex which in turn increases the foamability, emulsifying property and viscosity of solution. APG does not show any effect on its surface tension in the presence of nonionic polymers but its foamability and emulsifying properties are improved. Reduction in surface tension is not the only reason behind increased foamability in the presence of the polymer. Higher molecular weight polymers give a rich, creamy foam because of increased viscosity in the surfactant solution as compared to lower molecular weight polymers.