Micellization of Carboxylic Acid Gemini Surfactant and Its Interaction with Amino Acid Surfactant in Aqueous Solution

The carboxylic acid-type Gemini surfactant (CGS12) was synthesized, and its micellization in aqueous solution at different pH values at 25.0 °C was investigated. The results show that the critical micelle concentration (CMC) of CGS12 at different pH values is only 10⁻⁶ order of magnitude, and the pH has little effect on the CMC. Moreover, the interaction of CGS12 with amino acid surfactant of sodium N-lauroyl sarcosinate (SLS) at 25.0 °C and pH 7.0 was investigated using surface tension, dynamic light scattering (DLS), cryogenic transmission electron microscopy (Cryo-TEM), and Ross–Miles foam measurements. The CGS12/SLS mixture shows a low CMC, and as a whole the CMC value becomes smaller with increasing molar fraction of CGS12 (X_CGS12). Under different X_CGS12, the mixtures form soluble aggregates with different hydration radii (R_h). Moreover, the mixture aggregates are mainly in the form of vesicles. The foaming height of CGS12 is worse than that of SLS, but the CGS12/SLS mixture has good foaming stability. This work reveals that the surfactant mixture has good surface activity and good foam stability.     

The effect of some foam boosters on the foamability and foam stability of anionic systems

The foaming properties of anionic surfactant solutions containing a nonionic surfactant, fatty acid N-methyl-ethanolamide (NMEA), were investigated. Foamability, which is the foam-generating power at the initial stage of foaming, was measured by a laboratory-built foam-testing apparatus, and also by the conventional Ross-Miles test NMEA synergistically increased the foamability of anionic surfactant solutions, particularly when small amounts of NMEA were added. Shorter hydrocarbon chain lengths of NMEA, such as N-octanoyl-N-methylethanol (NMEA-08) and N-decanoyl-N-methylethanol (NMEA-10), showed better performance in the laboratory-built foam tester. The results of the Ross-Miles evaluation, however, were completely opposite. Compared with commercial nonionic boosters, such as fatty acid monoethanolamide, fatty acid diethanolamide, and lauramidopropyldimethylbetaine (LPB), NMEA was the most effective for increasing foamability of the solution at the initial stage. The most popular amphoteric foam booster, LPB, did not increase foamability but likely generated the initial foam volume on the Ross-Miles test as a result of foam film stabilization. From these results, a foam-boosting mechanism of NMEA different from that of LPB is suggested.     

Study on aqueous film-forming foam extinguishing agent based on fluorocarbon cationic–hydrocarbon anionic surfactants mixture system

Fluorocarbon surfactants were the main components of aqueous film-forming foam extinguishing agents (AFFF). Unfortunately, the widely used fluorocarbon surfactant perfluorooctane sulfonate (PFOS) was limited due to its toxicity, bioaccumulation and biodegradability. In this paper, an environmentally friendly quaternary ammonium cationic fluorocarbon surfactant with high surface activity and simple synthesis route was reported. The surface performance and aggregation behavior of the mixed solution of this fluorocarbon surfactant and sodium n-octyl sulfate were studied by means of surface tension meter and transmission electron microscope (TEM). The results showed that the synergistic effect of sodium n-octyl sulfate and this fluorocarbon surfactant was significant, and many vesicles could be observed in the mixed solution with the concentration of 0.1 mol/L under TEM. Subsequently, three environmental friendly AFFF formulations (F-1, F-2, F-3) were designed with the mixture of the fluorocarbon surfactant, sodium n-octyl sulfate and lauryl betaine BS-12 as foaming agent. Through its foam performance test, it could be seen that F-3 showed relatively excellent foam performance. The initial foam height h₀ was 70 mm, the 25% drainage time was 315 s, the extinguishing time was 28 s, and the burn-back time was 720 s. This kind of fire extinguishing agent had the potential of fire protection application.     

R_(12)TAC-SDS混合溶液的表面张力和泡沫性能

测定了 3 十二烷氧基 2 羟丙基三甲基氯化铵 (R12 TAC)和十二烷基硫酸钠 (SDS)复配体系的表面张力和泡沫性能。实验表明 ,复配体系的CMC及γCMC均低于单一组分。当R12 TAC和SDS以等量比复配时 ,体系表现出良好的泡沫性能。其中起泡性参数Cs为 1.99mmol/L ,Rmv 为0 86 ,稳泡性参数Ct为 2 .5 0mmol/L ,t1/ 2 m 为 91.5s。对相互作用参数的计算表明 ,该复配体系具有强烈的增效作用     

碳氢/有机硅/低碳醇三元系泡沫及抑制煤自燃的效果分析

泡沫灭火剂是常用的火灾扑救方法之一,但常规泡沫灭火剂存在半衰期短,析液、聚并迅速而影响灭火效能的问题,基于火灾化学和活性剂技术,提出碳氢表面活性剂SDS、有机硅表面活性剂LS-99和低碳醇的三元系泡沫体系,并系统探究碳氢/有机硅/低碳醇的复配配比。通过表面张力、发泡高度、稳泡系数的大量测试,发现LS-99的临界胶束浓度为0.0083%。LS-99和SDS二元系在降低表面张力、提升发泡高度和稳泡系数方面具有良好的协同增效作用。在此基础上引入适量浓度的能够延缓泡沫析液、聚并的异丁醇,设计出了性能优良的碳氢/有机硅/低碳醇泡沫灭火剂。LS-99、SDS和异丁醇的质量分数为0.1%时,测试结果表明SDS/LS-99/醇三元系泡沫的发泡倍数可达52.5倍,25%析液时间可达210 s,300 s时的稳泡系数高达0.958,半衰期远超常规泡沫。煤自燃的灭火抑制实验表明,SDS/LS-99/醇三元系泡沫作用下,煤自燃各反应阶段的活化能相较于空气氛围均增大,反应难度增强;最大失重速率下降,反应剧烈程度减弱。初期吸热阶段的吸热量为78.3 J/g,大于空气氛围下煤氧复合的吸热量,吸热增幅高达2.16倍。放热阶段的放热量为1765.4 J/g,相较于空气氛围放热降幅达到15.15%,表明SDS/LS-99/醇三元系泡沫对煤自燃具有良好的灭火效果。     

中低温低泡除油剂的研究

研究了一种能在低温下除去金属表面油污的低泡除油剂.采用复配试验筛选了合适的低泡非离子表面活性剂.通过正交试验研究了各组分对除油效果的影响,得到中低温低泡除油剂的最佳配方为:DOWFAX 2A1 1.0 g/L,TX-10 1.25 g/L,天然植物醇油烷氧基化物0.5 g/L,EP2445 0.25 g/L,Na2Si...     

Surface Activity and Performance Properties of Gemini Salts of Linear Alkylbenzene Sulfonate in Aqueous Solution

Gemini salts of linear alkylbenzene sulfonate (LABS) were prepared by neutralization of sulfonic acid with a series of low-molecular-weight diamines in aqueous solution. The equilibrium surface activity of Gemini salts of LABS was determined by measuring the surface tension as a function of surfactant concentration to determine the critical micelle concentration (CMC), surface tension at the CMC (γ_CMC), and the area per molecule at the air-water interface (Ų). Electrical conductivity was measured as a function of surfactant concentration to determine the CMC and counterion binding. Dynamic surface tension was measured using a bubble pressure tensiometer to infer the rate at which the surfactant migrates to the air-water interface. Equilibrium interfacial tension against mineral oil was measured using a spinning drop tensiometer. Dynamic interfacial tension was measured using a drop volume tensiometer. The surface tension, CMC, and interfacial tension of Gemini salts of LABS decreased compared to monovalent organic and inorganic salts. The CMC decreases with increasing molecular weight of the diamine spacer group. Dynamic surface and interfacial tension of Gemini salts of LABS are lower than monovalent salts. The foam volume of Gemini salts of LABS was determined using a high shear blender test. The foam volume of Gemini salts of LABS is lower than monovalent salts and depends on the size of the spacer group. Hard-surface cleaning was measured using artificial soil applied to white Formica tiles. Soil removal was determined by optical reflectance as a function of abrasion cycles. Gemini salts of LABS show reduced hard-surface cleaning performance compared to monovalent salts. Detergency of different types of soils on cotton and polyester/cotton fabric was determined by optical reflectance measurements. Gemini salts of LABS show improved cleaning performance compared to monovalent salts. Cleaning performance increases with increasing molecular weight of the diamine spacer group. In situ neutralization of LABS with organic diamines is a simple and efficient way to prepare anionic Gemini surfactants for industrial scale applications.     

皂荚素及其复配体系表面活性的研究

系统地研究了皂荚素单组份及其复配体系在常温下的来得及面张力及泡沫性能,以及温度、盐度、水硬度、pH值等因素对其表面活性的影响。结果表明皂荚素是一种性能优良的天然表面活性剂,具有强的耐盐和耐硬水能力,与其他常见的几种阴离子、阳离子、非离子型表面活性剂复配后,均具有显著的协同剂应。     

含多官能团Gemini表面活性剂的合成及性能

以氯乙酰氯、间苯二甲酰氯、长链伯胺（碳链长度为8、12、14和16）和N,N-二甲基乙醇胺为原料合成了一系列含多官能团Gemini阳离子表面活性剂目标产物（I₈、I₁₂、I₁₄和I₁₆）。采用红外光谱和核磁氢谱对产物进行了结构表征。通过电导率法测量目标产物在不同温度下的临界胶束浓度（CMC），并计算出胶束的热力学参数（、、）；在298.15K条件下，通过表面张力法测定目标产物的表面张力（γ_CMC），并探讨了目标产物的泡沫性能和乳化性能。结果表明：目标产物有较低的临界胶束浓度值（CMC），在298.15K条件下，最低CMC达到0.05mmol/L；I₁₆的γ_CMC最低为36.14mN/m；泡沫性和乳化性测试结果表明，在298.15K条件下，I₈的起泡能力最好，I₁₂和I₁₄的稳泡性最好，均达到100%；目标产物对苯和二甲苯具有很好的乳化性能，其中I₁₂对二甲苯的乳化性能最好，乳化时间为900s，I₁₆对苯的乳化性能最好，乳化时间为629s。     

N-十二烷基葡糖酰甲胺香波体系的泡沫及增稠性能

研究了MeGA-12(N-十二烷基葡糖酰甲胺)的加入对AES和铵盐体系香波黏度和泡沫的影响，并与市购的6501作了比较。实验结果表明，在NaCl质量分数为0．3％时，MeGA-12加入对铵盐体系香波的增稠效果要比6501好；在与AES和铵盐复配使用并用NaCl调黏，达到相同黏度时MeGA-12体系加入的NaCl要少；它与AES和铵盐复配时都具有良好的发泡力和稳泡力。     

牛血清白蛋白和溶菌酶混合溶液的泡沫性能与其浓度的关系

生物表面活性物质的浓度对其溶液的泡沫性能有很大的影响。泡沫性能包括起泡性和泡沫稳定性。本文以初始泡沫高度和泡沫半衰期分别表征了起泡性和泡沫稳定性。首先利用Szyszkowski扩展方程和Rosen的经验模型,导出了低于临界胶束浓度(CMC)时,两种表面活性物质混合溶液的初始泡沫高度与其各自浓度的关系式;然后根据泡沫相中溶液的重力势能和表面能随气泡破裂而减小的规律,建立了低于CMC时两种表面活性物质混合溶液的泡沫半衰期与其各自浓度的关系式;最后用牛血清白蛋白(BSA)和溶菌酶(LZM)作为实验物系考察了这两种关系式的准确性。结果表明这两种关系式能准确预测BSA和LZM混合溶液的泡沫性能。在BSA和LZM混合溶液中,BSA能显著影响溶液的泡沫性能,而LZM对溶液泡沫性能的影响小。     

Molecular dynamics simulation on the structure–activity relationship between the Gemini surfactant and foam properties

The structure–activity relationship between the molecular structure of Gemini surfactants and foam properties has not yet been deeply revealed. In this study, we clarified for the first time the structure–activity relationship between foam properties and molecular structure of Gemini surfactant by discussing the variation characteristics of parameters such as free energy of interface formation, radial distribution function, and mean square displacement calculated by molecular simulation method. The research results show that (1) the Gemini surfactant with the sulfonic acid head group has the most excellent foam properties; (2) the foam properties increase monotonously with the increase of the hydrophobic tail chain length; (3) the foam properties decrease monotonously with the increase of the spacer group length. It is hoped that this article can further broaden the application range of surfactants as foaming agents in industrial fields such as oil and gas exploitation.     

泡沫性能的测试和评价方法进展

综述了测试泡沫性能——主要是溶液的起泡能力和泡沫稳定性的方法以及评价手段;介绍了常用的起泡方式及检测手段,包括体积法、电导率法和压力法,讨论了各方法的优缺点;并叙述了评价溶液起泡能力和泡沫稳定性手段的进展;提出了选择合理的评价方法以客观完善的对泡沫性能进行评价的必要性。     

Surfactant properties of low molecular weight phospholipids

Surface tensions, critical micelle concentrations (CMCs), contact angles on hydrophobic polyethylene, and foaming characteristics of phosphatidic acids, phosphatidylcholines, phosphatidylethanolamines, and phosphatidylglycerols were measured to determine their suitability as substitutes for traditional surfactants. These phospholipids have fatty acid chains of 5 to 12 carbon atoms, a range over which they are soluble at room temperature. Their surface tensions decrease with increasing concentrations until their CMCs are reached, above which their plateau surface tensions are as low as 21 mN/m, indicating excellent surface activities. In general, plateau surface tensions decrease with increasing chain length within each phospholipid type. The classical relationship for In CMC vs. chain length is followed with slopes typical of anionic surfactants for phosphatidic acids and phosphatidylglycerols and resembling zwitterionic surfactants for phosphatidylcholines and phosphatidylethanolamines, consistent with the charge on the hydrophilic group. The wetting capabilities of aqueous solutions on polyethylene are good and foam heights and stabilities are high, the latter two properties being comparable to traditional anionic (sodium dodecylsulfate) and nonionic (octylphenol polyethoxylate) surfactants. Some anomalies are observed regarding the effect of chain length on wetting and foaming, probably due to the depletion effect. Many phospholipids slowly degrade in aqueous solution. We conclude that short-chain phospholipids exhibit excellent surfactant properties and may be useful in many applications.     

一种新型蛋白质混凝土发泡剂的研制及性能研究

以啤酒废酵母为原材料,制备一种新型的蛋白质混凝土发泡剂并通过正交实验对水解条件进行优化。研究了发泡剂以及不同添加剂对其发泡性能和泡沫稳定性的影响,结果表明表面张力是发泡剂发泡性能提升的重要因素,但对泡沫稳定性没有决定性影响;适当增加溶液黏度可延长其泡沫稳定时间,其中添加卡拉胶0.1%/100 mL发泡液时,发泡体积为725 mL,其泡沫稳定时间也超过了25 h。     

Surface Properties and Solubility Enhancement of Anionic/Nonionic Surfactant Mixtures Based on Sulfonate Gemini Surfactants

As a class of novel surfactants, Gemini surfactants usually exhibit fairly excellent interfacial properties in aqueous solutions on account of the unique structure. They have significant application and development potential for industrial production. However, the mixing properties of Gemini surfactants with conventional surfactants are the key to their application. The equilibrium surface tension curves of anionic/nonionic surfactant mixtures based on the sulfonate Gemini surfactant (SGS-12) were measured using the Wilhelmy Plate method. The parameters of surface adsorption, the interaction parameters between anionic and nonionic surfactants, and the thermodynamic parameters of micelle formation were calculated from the corresponding equations. In addition, the dynamic surface tension (DST) curves of anionic/nonionic surfactant mixtures were examined through bubble profile analysis, and the diffusion performance parameters were acquired from empirical formulas. The solubilization of pyrene in micelle solutions was studied using UV–vis absorption spectroscopy. The results show that the interaction parameters of all anionic/nonionic surfactants are negative, indicating that there is a synergistic effect on reducing the surface tension. For the SGS-12/OP-10, SGS-12/Tween 80, SGS-12/AEO9, and SGS-12/APG0810 mixtures, the optimum mixing ratios are 6:4, 7:3, 7:3, and 8:2, respectively. The thermodynamic data of micelles show that the formation of mixed micelles for SGS-12/APG0810 mixtures is an enthalpy-driven process. The tendency of DST curves of the SGS-12/APG0810 mixture is similar to that of SGS-12. In comparison with single-surfactant solutions, the anionic/nonionic surfactant mixtures show stronger solubilization capacity toward pyrene.     

直链型偶氮苯聚氧乙烯醚稳泡剂的制备及表面活性

以4-羟基偶氮苯、1,2-二溴乙烷、PEG-600为原料,合成直链型偶氮苯聚氧乙烯醚非离子表面活性剂(PEP-600)。通过红外光谱和核磁共振氢谱表征了其结构,并测试了其表面活性。结果表明,PEP-600临界胶束浓度(CMC)为4.99×10~(–3) mol/L,在CMC处表面张力为48.09 mN/m,饱和吸附量为2.48×10~(–3) mmol/m~2,亲水亲油平衡值(HLB)为14.20。将PEP-600与0.1 g/L的十二烷基硫酸钠复配最大发泡比为12,泡沫半衰期为220s左右,直链型分子结构的PEP-600在泡沫液膜表面排列紧密,具有优异的起泡性能,可用作泡沫染整稳泡剂。     

全氟辛酸三烷基铵的表面活性、润湿及泡沫性能

通过测定全氟辛酸三甲/乙/丙/丁铵[C7F15COONH(CnH2n+1)3,n=1,2,3,4,简称为TMHPFO,TEHPFO,TPHPFO,TBHPFO]水溶液的表面张力、泡沫及在石蜡表面的接触角,研究三烷基铵反离子对氟表面活性剂的影响.表面张力实验表明,反离子为三甲/乙/丙铵离子时,氟表面活性剂具有极高的表面活性,其表面活性不仅高于普通的全氟辛酸盐(如钠盐),而且高于已报道的反离子为四烷基铵的全氟辛酸盐,说明反离子结构的很小改变对氟表面活性剂的表面活性有很大影响.在石蜡表面润湿性的规律为:TPHPFO>TEHPFO≈TMHPFO>TBHPFO.全氟辛酸三甲/乙/丙铵水溶液的发泡力和泡沫稳定度随着反离子增大而增强,说明反离子的碳氢链在表面吸附层的插入更利于发泡及泡沫稳定.TBHPFO受溶解度的限制导致表面活性相对较低,起泡性和润湿性极差.     

高效低泡净洗剂的研制与应用

对不同配方的发泡力、泡沫稳定性以及净洗效果的测试结果表明皂剂、烷基苯磺酸盐和平平加O按适当比例进行复配可以得到泡沫少、泡沫破灭快，净洗效果好的高效低泡净洗剂。     

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.