不同类型的离子表面活性剂对甲苯的增溶作用

通过电导法测定SDBS、CTAB、FMES 3种离子表面活性剂水溶液在25,30,35℃时的临界胶束浓度(CMC),并依据CMC和范特霍夫方程计算了3种体系下的ΔH■、ΔS■和ΔG■,测定无机盐(NaCl、Na_2SO_4)和有机物(乙醇、十二醇)对表面活性剂增溶甲苯的影响。结果表明,3种体系下ΔG■均为负,这说明3种表面活性剂在水溶液中均易于形成胶团;3种离子表面活性剂的CMC大小顺序与对甲苯溶解量的大小顺序不同,说明CMC大小并不是影响甲苯增溶的唯一因素;添加一定量有机物[n(乙醇)∶n(FMES)=1∶4]或者无机盐(0.2 mol/L浓度的NaCl)对甲苯增溶效果更好。     

不同类型的离子表面活性剂对甲苯的增溶作用

通过电导法测定SDBS、CTAB、FMES 3种离子表面活性剂水溶液在25,30,35℃时的临界胶束浓度(CMC),并依据CMC和范特霍夫方程计算了3种体系下的ΔH■、ΔS■和ΔG■,测定无机盐(NaCl、Na_2SO_4)和有机物(乙醇、十二醇)对表面活性剂增溶甲苯的影响。结果表明,3种体系下ΔG■均为负,这说明3种表面活性剂在水溶液中均易于形成胶团;3种离子表面活性剂的CMC大小顺序与对甲苯溶解量的大小顺序不同,说明CMC大小并不是影响甲苯增溶的唯一因素;添加一定量有机物[n(乙醇)∶n(FMES)=1∶4]或者无机盐(0.2 mol/L浓度的NaCl)对甲苯增溶效果更好。     

阴离子表面活性剂与阳离子表面活性剂的相互作用(Ⅱ)——稀溶液性质

介绍了阴离子表面活性剂与阳离子表面活性剂相互作用的稀溶液性质。在水溶液中,阴/阳离子表面活性剂混合体系因分子间极性基正/负离子的强静电吸引作用,易形成棒状胶束,浓度超过cmc后,可能发生聚集,出现浑浊、分相等情况,使用短链表面活性剂、引入聚氧乙烯链及非等摩尔复配在一定程度上可避免这种现象。均相阴/阳离子表面活性剂混合溶液,对非极性有机物的增溶存在增效作用,但对极性有机物的增溶能力则有可能下降;在一定浓度及混合比范围内还可能出现类似非离子表面活性剂的浊点效应。     

新型双子表面活性剂在三次采油中的应用研究

结合双子表面活性剂的结构及分类,综述其独特的性质,即高表面活性,良好的水溶性,高的增溶能力,优异的协同作用,独特的流变性,优良的润湿性等,介绍了几种三次采油用的特殊双子表面活性剂(合成工艺简单型,环保型,复配型),指出优化合成工艺,开展复配研究,提高产品产率,开发新型产品(如杂双子表面活性剂)是未来发展方向.     

不同因素对CTAB/TX-100微乳液相图的影响

用ε-β"鱼状"相图法研究了阳离子表面活性剂十六烷基三甲基溴化铵(CTAB)与非离子表面活性剂辛基苯酚聚氧乙烯(10)醚(TX-100)以不同摩尔比复配形成的CTAB/TX-100/醇/油/NaCl水溶液微乳液体系的相行为和增溶性能.结果表明,随着醇浓度的增加,体系由水包油型(O/W)(winsor Ⅰ or (2-)...     

含三嗪环阴离子Gemini表面活性剂的性能研究

研究了含三嗪环阴离子Gemini表面活性剂增溶、流变、溶致液晶、囊泡等性能。结果表明:增溶量随Gemini表面活性水基和联接基长度)对其水溶液的黏度有相同的影响;C6-2-C6、C8-2-C8、C8-3-C8、C8-4-C8、C8-6-C8、C12-2-C12在质量分数剂疏水链长度的增长而增大,C8-n-C8(n=23,4,6,)的增溶量随联接基长度增加而增加,C12-2-C12与SDS的复配体系比SDS的增溶量大,C12-2-C12与CTAB的复配体系比这2种表面活性剂单独使用时的增溶量小;Gemini表面活性剂溶液分子结构(疏分别为42.3%,37.8%,33.5%,30.4%,27.6%2,0.3%时均产生层状的溶致液晶;0.01 mol/L的单一Gemini表面活性剂水溶液均不能形成囊泡,而当n(C12-2-C12)∶n(CATB)为8∶2或9∶1时,复配体系的水溶液形成了大量的囊泡结构。     

琥珀酸二辛酯磺酸钠对海星皂苷在超临界CO2中的增溶作用

利用琥珀酸二辛酯磺酸钠(AOT)/混合醇/水溶液为助溶剂,以乙醇助溶剂为参照,考察了表面活性剂对海星皂苷在超临界CO2介质中的增溶作用。探讨了表面活性剂浓度、助表面活性剂组成、复合表面活性剂配比等因素对海星皂苷增溶的影响,结果表明:摩尔比为4∶1、浓度为0.05 moL/L的AOT/辛基酚聚氧乙烯醚(OP-10)复配表面活性剂,对海星皂苷具有良好的选择性增溶作用,海星皂苷的萃取率为2.40%,提取物中海星皂苷质量分数为58.99%,分别是使用乙醇助溶剂的4.08、2.18倍。     

表面活性剂L-113A增溶能力的测定

采用分光光度法研究高分子表面活性剂L-113A的增溶能力，用一定量的表面活性剂将苯增溶在水中，当体系中苯的含量超过表面活性剂的增溶极限时，便产生浑浊，溶液光密度迅速增大，由此来测定表面活性剂的增溶能力。由实验得出：在溶液含苯量最小时就已经超过了表面活性剂的增溶极限，因此表面活性剂L-113A几乎没有增溶能力。     

非离子表面活性剂TX114浊点萃取D2EHPA的规律

引言浊点萃取[1-2]是利用表面活性剂水溶液的增溶和分相行为实现溶质富集的分离技术。由于分相后表面活性剂的富集相(亦称凝聚相)与水相的体积比非常小(0.007～0.04)[3],所以,对于被增溶的物质能够提供非常高的富集倍数和萃取效率。目前浊点萃取技术主要广泛应用于痕量有害物质     

SDS／C16 mimBr复配中相微乳液的增溶性能研究

运用δ-γ"鱼状"相图法,以SDS-C16mimBr/正丁醇/正辛烷/2.5% NaCl水溶液四元体系微乳液为例,研究了十二烷基硫酸钠(SDS)与离子液体表面活性剂溴代1-十六烷基-3-甲基咪唑(C16mimBr)复配体系的增溶性能.     

Gemini表面活性剂的特性及耐盐活性研究

研究了疏水链长度不同和联接基长度不同的7种系列阴离子Gemini表面活性剂的表/界面活性。它们的表面张力和临界胶束浓度表明它们有很好的表面活性。它们有非常好的抗一价、二价盐的能力,在20%以上的NaCl盐水中仍能溶解。用高矿化度的中原油田盐水配制的活性剂溶液与原油间的界面张力能达到超低,表明它们可应用于特高矿化度油藏提高采收率。     

Hydrotrope-Induced Enhancement of Room Temperature Surface Activity for High Krafft Point Fluorinated Surfactants

Potassium perfluorooctane sulfonate (KPFOS) and sodium perfluorooctane sulfonate (NaPFOS) exhibit poor surface activities in aqueous solution at room temperature because of their high Krafft points. In this work, we attempted to increase the solubility of KPFOS and NaPFOS and consequently improve their surface activities at room temperature with sodium p‐methylbenzene sulfonate (BS) and urea, which are typical hydrotropes in industrial applications. The effects of BS and urea on the surface tension of the aqueous solutions of KPFOS and NaPFOS were investigated at 25 °C. When the hydrotropes were added, the effectiveness of KPFOS and NaPFOS in surface tension reduction was greatly enhanced and KPFOS showed higher efficiency in surface tension reduction than NaPFOS. On the other hand, BS had much stronger ability than urea to reduce the surface tension of KPFOS and NaPFOS in water. In particular, with the assistance of BS the minimum surface tension of KPFOS approached 19 mN/m at 25 °C. It was worth noting that in the presence of BS, the surface tension of an apparently “saturated” solution (i.e., with coexisting surfactant solid) continuously decreased with increasing surfactant concentration. This behavior was ascribed to enrichment of branched PFOS isomers in aqueous phase with the assistance of BS, as evidenced by high‐resolution ¹⁹F NMR. Hydrotropes were able to recover the inherent character of KPFOS and NaPFOS as highly surface‐active fluorinated surfactants by increasing the solubility of branched isomers. This is an easy way to enhance the effectiveness in surface tension reduction at room temperature for fluorinated surfactants with high Krafft points.     

表面活性剂CTAB与NaSal相互作用性质的研究

通过粘度、电导率、表面张力以及紫外吸收光谱等手段,研究了阳离子表面活性剂十六烷基三甲基溴化铵（CTAB）与水杨酸钠（NaSal）之间的相互作用。结果表明,CTAB与NaSal之间有一定的相互作用,从而使体系表现出较强的粘度行为,并导致其混合溶液的最大紫外吸收峰发生了红移,同时NaSal／CTAB溶液的电导率以及表面张力也发生了一定的变化。     

全氟烷基表面活性剂吸附特性研究

针对全氟烷基季铵碘化物(Le-134)、全氟烷基磷酸酯(Le-107)和全氟烷基聚醚(Le-180)三种表面活性剂水溶液的平衡态表面张力和吸附动力特性进行了研究。临界胶束浓度的大小关系为Le-180 (15×10^-6) -6) -6);饱和吸附量Г_max大小关系为 Le-107 相似文献   

Synthesis and Self-Assembly Behavior of Comb-Like Surfactant Polymethyl Methacrylate-g-Methoxy Polyethylene Glycol

Comb-like surfactant of polymethyl methacrylate-g-methoxy polyethylene glycol (PMMA-g-MPEG) with well-defined structure was synthesized and characterized by FT-IR, ¹H NMR and gel permeation chromatography. Its surface activity and aggregation behavior in aqueous solution were investigated by surface tension measurement, dye encapsulation experiment, transmission electron microscopy (TEM) and dynamic light scattering (DLS). The CMC and surface tension at the CMC of PMMA-g-MPEG were 0.2 g/L and 47 mN/m, respectively. DLS and TEM analysis revealed that PMMA-g-MPEG could self-assemble into spherical micelles with the average hydrodynamic diameters in the range from 20 to 300 nm in aqueous solution.     

Surface adsorption in the mixtures of sodium dodecylsulphate and oxyethylenated nonylphenol with different oxyethylenation degrees

The effectiveness of surface adsorption in an aqueous solution of mixtures of surfactants composed of an anionic surfactant, sodium dodecylsulphate, mixed with a nonionic one, polyoxyethylenated nonylphenol, was studied. Their behavior was compared separately. This surface adsorption was characterized by the values of the surface tension at 25°C of the total concentrations below, but near to the critical micelle concentration (CMC) in the mixtures mentioned. These were obtained as a function of different proportions of surfactants in the mixture and different chain lengths of nonionic polyoxyethylenated surfactant. The total surface excess concentrations of the surfactant mixtures and the average of molecular area per surfactant species at the aqueous solution/air interface were calculated. Finally, the values were analyzed vs the above parameters. Presented at the XDCth Meetings of CED/AID, Granada, Spain, March, 1988.     

硫酸酯盐双子表面活性剂的合成和界面张力的研究

实验室条件下,以长链羧酸(月桂酸)、聚乙二醇等为主要原料,通过赫尔-乌尔哈-泽林斯基反应等和酯化反应,用醚键加入方式加入联接基团,用浓硫酸加成反应加入硫酸酯键,从而在实验室条件下合成具有特殊结构的双子表面活性剂-GA12-S-12.通过用旋转液滴法测合成的硫酸酯盐阴离子双子表面活性剂的表面张力,测得其临界胶束浓度(CMC)为438 mg/L,临界胶束浓度下表面张力为30.9 mN/m,并对比十二烷基硫酸钠水溶液表面张力,显示GA12-S-12[低聚二醇(α-硫酸酯钠)月桂酸双酯阴离子双子表面活性剂]具有更优的表面活性.进一步配制不同浓度的GA12-S-12表面活性剂溶液,测定它们与长庆五里湾原油的界面张力,效果显示其适用于五里湾区原油采收率的提高.     

无机盐对磺酸盐型双子表面活性剂溶液表面性能的影响

在(30±0.2)℃下,用直接观察法、表面张力法和旋转液滴法考察了不同无机盐(NaCl、CaCl2和MgCl2)对磺酸盐型双子表面活性剂DJ溶液溶解性、临界胶束浓度(CMC)值和界面张力的影响。结果表明,磺酸盐型双子表面活性剂DJ具有良好的抗盐性,溶解度可以达到20 000 mg/L以上;在低盐度范围时(小于500 mg/L),随着无机盐质量浓度的增加,表面活性升高,CMC降低;随着阳离子(Na+、Ca2+和Mg2+)价数的增加,CMC降幅增大,且Ca2+的影响程度大于Mg2+;在无机盐质量浓度达到10 000 mg/L时,CMC呈上升趋势;无机盐的加入使溶液界面张力先降后升,然后趋于平稳。无机盐质量浓度在100～1 000 mg/L内,磺酸盐型双子表面活性剂DJ溶液的界面张力可以达到最低。     

Synthesis and Micellization Properties of New Anionic Reactive Surfactants Based on Hydrogenated Cardanol

We report the synthesis, characterization and micellization properties of two anionic reactive surfactants based on 3-pentadecyl phenol obtainable from a renewable resource, cardanol. The synthesis is achieved through simple chemical transformations, first converting the phenol to the acrylate that is sulfonated in a second step. The products were characterized by elemental analysis and spectroscopic techniques. The surfactant properties of the sulfonated acrylates were measured and compared with the standard non-reactive anionic surfactant sodium dodecyl sulfonate. The micellization behavior of aqueous solutions was studied using conductivity, surface tension measurements, and the fluorescence probe technique based on diphenyl hexatriene. Characterization by surface tension measurements facilitated the determination of basic surfactant properties like the critical micelle concentration (CMC), the surface tension at the CMC, surface excess and area per surfactant molecule. The Gibbs free energy of micellization showed a negative value suggesting spontaneous micellization in aqueous solution. The micellization of the surfmer with an ethylene spacer between the phenyl ring and the acrylate group seems to be enhanced as indicated by the lower surface excess and lower free energy. Its CMC was also lower.     

A Star-Shaped Anionic Surfactant: Synthesis,Alkalinity Resistance,Interfacial Tension and Emulsification Properties at the Crude Oil–Water Interface

In this research, a star‐shaped surfactant was synthesized through the chlorination reaction, alkylation reaction and sulfonation reaction of triethanolamine, which is composed of three hydrophobic chains and three sulfonate hydrophilic groups. The critical micelle concentration (CMC) of the surfactant was measured by the surface tension method, and the results showed that it had high surface activity with CMC of 5.53 × 10^?5 mol/L. The surfactant was superior in surface active properties to the reference surfactants SDBS and DADS‐C₁₂. The interfacial tension (IFT) of the studied crude oil–water system (surfactant concentration 0.1 g/L, NaOH concentration 0.5 g/L, and experimental temperature 50 °C) dropped to 1.1 × 10^?4 mN/m, which can fulfil the requirement of surfactants for oil displacement. An aqueous solution of the surfactant and crude oil was emulsified by shaking, which formed a highly stable oil‐in‐water (O/W) emulsion with particle size of 5–20 μm. The oil displacement effect was almost 12%.