改进的UNIQUAC模型在非离子表面活性剂溶液中的应用

将非离子表面活性剂划分为链节,建立了一个计算混合Gibbs自由能的分子热力学模型,对不同温度下的5个非离子表面活性剂-水体系的临界胶束浓度进行了关联,并利用得到的参数预测了不同温度下其他14个表面活性剂体系的临界胶束浓度,关联与预测结果均令人满意。与Chen-NRTL模型相比,本模型计算精度较好,具有预测功能。     

表面活性剂协同效应的研究(英文)

新型表面活性剂的开发研究及现有品种的复配是表面活性剂研究领域中的两个主要方向。对洗涤剂中常用的表面活性剂 :烷基聚氧乙烯醚硫酸钠 (AES)、椰子油酰胺丙基甜菜碱 (KBT)和椰子油二乙醇酰胺 (CDEA)的复配进行了研究。采用滴体积法测定了混合溶液AES/KBT和AES/CDEA的表面张力σ ,再根据σ与溶液浓度C曲线 ,求得溶液的临界胶团浓度cmc、C =cmc时溶液的表面张力σcmc及σ =35mN·m-1时溶液的浓度C35。溶液的起泡性和泡沫稳定性则利用根据Ross -Mile原理自制的装置来测定。实验结果显示 ,在一定混合比时 ,混合溶液的cmc值比相应的任一纯组分的cmc0i 都要低 ,C35也低于纯组分的C035,说明两复配体系均有形成胶团和降低表面张力效率的协同效应。最小cmc值所对应的复配比例 (摩尔比 )为AES/KBT =0 46∶0 5 4,AES/CDEA =0 42∶0 5 8。实验结果还显示 ,混合溶液的起泡性和泡沫稳定性均有改善 ,特别是泡沫稳定性     

新型Gemini表面活性剂与SDS复配性能研究

利用K100表面张力仪测试新型阴离子Gemini表面活性剂(IXC8)与传统阴离子表面活性剂十二烷基硫酸钠(SDS)复配体系的表面张力,研究了不同温度(25、30、35、40℃)下复配体系的相互作用。结果表明,35℃时IXC8/SDS复配体系0.3∶0.7和0.7∶0.3在降低表面张力的效能方面存在增效作用;25℃时复配体系0.5∶0.5以及30℃和35℃时的全部配比在降低表面张力的效率方面存在增效作用;所有的复配体系均在形成胶束能力方面存在增效作用。     

复合表面活性剂的表面特性：临界胶束浓度的测定

用电导、表面张力和折光指数法估算了十二烷基硫酸钠（ＳＬＳ）、十二烷基苯磺酸钠（ＳＤＢＳ）和辛基酚聚氧乙烯基醚（ＯＰ）复合乳化剂的临界胶束浓度（ＣＭＣ）。发现，ＳＬＳ／ＯＰ和ＳＤＢＳ／ＯＰ的ＣＭＳ值约为１０＾－３ｇ／ｍｌ数量级，数据与乳化剂纯度有关，但与复合乳化剂中两者的比例无关。同时对三种测定方法作了评价。     

一种酯型双子表面活性剂的合成及其协同效应

通过酯化、溴代和季铵化反应,合成了以乙氧基为联接基的酯型双子(Gemini)阳离子表面活性剂N,N′-双(二甲基十二酸乙酯基)乙醚溴化铵([C11H23COOCH2CH2N (CH3)2CH2CH2OCH2CH2N (CH3)2CH2CH2OOCC11H23].2Br-,Ⅱ-12-EO2)。以表面张力法和稳态荧光法考察了Ⅱ-12-EO2与十二烷基硫酸钠(SDS)复配体系在40℃时0.1 mol.L-1溴化钠水溶液中的表面化学性质和胶束化行为。得到Ⅱ-12-EO2的临界胶束浓度(cmc)为1.25×10-4mol.L-1,最低表面张力(γcmc)为28.4 mN.m-1。采用稳态荧光法以芘(Py)为荧光探针,Ⅱ-12-EO2的胶束栅栏层的微极性,较一般表面活性剂大,达到1.4,与SDS的复配体系在1.2左右;以十二烷基溴化吡啶为猝灭剂,测定体系的胶束聚集数为15。运用非理想混合表面活性剂分子相互作用理论计算出Ⅱ-12-EO2与SDS复配体系的相互作用参数(β),复配体系具有降低表面张力效率、形成胶束能力和降低表面张力能力方面的协同效应。     

双基表面活性剂的性质与结构的研究

二聚(dimeric)和齐聚(oligomeric)表面活性剂是一类新一代的表面活性剂,在基础研究和生产实践中已逐步走向成熟。本文从最新的研究成果出发,着重于临界胶束浓度(critical micelle concentration,标记为Ccmc)和微观胶束结构两个方面,采用比较的观点和方法,阐述异揭示了其内在的规律和研究与应用前景。     

表面活性剂CMC的化学发光法测定

本文选用鲁米诺和光泽精两个化学光体系测定了表面活性剂TPB、CTAB、STAB、SDS和聚乙二醇辛基苯基醚（乳化剂OP）的CMC，所得结果与文献报道值一致。     

化学清洗与表面活性剂

叙述了表面活性剂在化学清洗中的作用，列举了大量工业应用的实例简介了表面活性剂的基本知识，对化学清洗中有效选择表面活性的原则提出浅见     

电导法测定表面活性剂溶液的临界胶束浓度

本文用电导法测定了十二烷基磺酸钠在４０℃和６０℃时的临界胶束浓度（ＣＭＣ），根据“相分离模型”计算了４０℃时十二烷基硝酸钠溶液的胶束形成标准焓变（△Ｈｍ），标准吉布斯自由能变化（△Ｇｍ）和标准熵变（△Ｓｍ）。     

复配表面活性剂的生成及对热力学函数的探讨

本文应用环法对阴离子表面活性剂（十二烷基苯磺酸钠以下用Ｃ１２示）和非离子表面活性剂（Ｔｒｉｔｏｎ－１０）所形成的复配体系的表面性质进行了研究，产通过有关数据处理得到一系列的热力学函数值，应用物理化学的基本原理，对一些现象作了解释。     

Molecular thermodynamic model for compounding of multiple surfactants

Surfactants are widely used in the actual industrial production. Generally, it is a compound system of multiple surfactants to make use of the characteristics of different components, so that the compound system has better performance than a single surfactant. The compounding mechanism of multiple surfactants is still an interesting topic. In this paper, experimental and theoretical models are used to study the synergistic effect among the components of mixed surfactants. Firstly, based on Flory-Huggins theory, the molecular thermodynamic model of the multi-component surfactant system is derived. The interaction parameters of the two systems are correlated through the experimental data of the binary system. The critical micelle concentration (cmc) of the multi-component system and the phase composition of the mixed surfactant micelle can be predicted. The calculated results of the three-component surfactant system model are in good agreement with the experimental values.     

Surface and thermodynamic studies of N-alkkyl N-trimethylsilane ammonium chloride surfactants

N-Dodecyl N-trimethylsilane ammonium chloride, N-tetradecyl-N-trimethylsilane ammonium chloride, N-hexadecyl-N-trimethylsilane ammonium chloride, and N-octadecyl-N-trimethylsilane ammonium chloride were prepared. Surface properties, particularly critical micelle concentration (CMC), effectiveness, maximum surface excess, and minimal surface area, were determined at different concentrations at 20, 35, 50, and 65°C, respectively. From electrical conductivity data, degrees of dissociation and dissociation constants at various concentrations were determined. Free energies, enthalpies, and entropies of micellization and adsorption of the surfactants in aqueous solution were studied.     

Inhibitory effect of non-ionic surfactants of the TRITON-X series on the corrosion of carbon steel in sulphuric acid

The corrosion inhibition characteristics of non-ionic surfactants of the TRITON-X series, known as TRITON-X-100 and TRITON-X-405, on stainless steel (SS) type X4Cr13 in sulphuric acid were investigated by potentiodynamic polarisation measurements. It was found that these surfactants act as good inhibitors of the corrosion of stainless steel in 2 mol L⁻¹ H₂SO₄ solution, but the inhibition efficiency strongly depends on the electrode potential. The polarisation data showed that the non-ionic surfactants used in this study acted as mixed-type inhibitors and adsorb on the stainless steel surface, in agreement with the Flory-Huggins adsorption isotherm. Calculated ΔG_ads values are −57.79 kJ mol⁻¹ for TRITON-X-100, and −87.5 kJ mol⁻¹ for TRITON-X-405. From the molecular structure it can be supposed that these surfactants adsorb on the metal surface through two lone pairs of electrons on the oxygen atoms of the hydrophilic head group, suggesting a chemisorption mechanism.     

利用荧光素异硫氰酸酯检测季铵盐阳离子表面活性剂的方法

使用荧光素异硫氰酸酯（FITC）实现了对季铵盐阳离子表面活性剂（QAS）在水溶液中临界胶束浓度（CMC）的准确测量及其在CMC以下的浓度定量。用该法测得十二烷基三甲基溴化铵（DTAB）和十六烷基三甲基溴化铵（CTAB）在水中的CMC分别为12～13 mmol·L^-1和0.70～096 mmol·L^-1,与电导率法、表面张力法和芘荧光法的检测值相近。对DTAB和CTAB的检测下限分别是011 mmol·L^-1和1.7 μmol·L^-1,定量范围分别为0.11～9.73 mmol·L^-1（0.034～3.0 g·L^-1）和1.7 μmol·L^-1～0.27 mmol·L^-1（6.2×10^-4～0.1 g·L^-1）。结果表明,使用FITC荧光探针检测QAS具有安全、简便、灵敏度和准确度高的优点。     

Adhesion of anionic surfactants to polymer surfaces and low-energy materials

To study the adhesion of the anionic surfactant sodium dodecyl sulfate (SDS) to various materials, a schematic molecular model of SDS was used which optimally correlates with its critical micelle concentration (c.m.c.) values under various conditions. Using the surface tension components and parameters of (a) the SDS apolar and polar moieties and (b) the polymeric surfaces of cellulose and nylon, the energy of adhesion of SDS to these polymeric surfaces as well as to a typical low-energy material (greasy dirt) in the guise of hexadecane was determined. It could be quantitatively shown (using a surface-thermodynamic approach) that SDS, in water, adheres more strongly to the low-energy (greasy dirt) compounds than to the polymeric materials. The c.m.c. of SDS was derived directly from the surface tension components and parameters of its apolar and polar moieties, and the ζ potential of its polar heads. The c.m.c. values obtained using this model correlate well with the published c.m.c. values obtained experimentally at different ionic strengths.     

Effectiveness of some non ionic surfactants as corrosion inhibitors for carbon steel pipelines in oil fields

The ability of new synthesized non ionic surfactants (I and II) to protect carbon steel in acid chloride solution was investigated using potentiostatic polarization, open circuit potential, weight loss and surface tension measurements. The experimental results showed that these inhibitors revealed a very good corrosion inhibition even at low concentrations. The percentage inhibition efficiency (η%) increases by increasing the inhibitor concentration until the critical micelle concentration (cmc) is reached. It was found that, the adsorption ability of the surfactant molecules on carbon steel surface increased with the increase of the molecular size of the surfactant. Potentiostatic polarization curves indicate that the inhibitors under investigation act as mixed type. Finally, the mechanism of carbon steel dissolution in acidic medium was discussed both in absence and presence of the inhibitor molecules.     

双子(Gemini)表面活性剂合成及研究进展

综述了阳离子型、阴离子型、非离子型和两性离子型四类双子表面活性剂的合成及研究进展,指出未来双子表面活性剂研究的主要方向为获得更高的表面活性、降低合成和使用成本、不同类型的表面活性剂协同强化、提高安全环保性和拓宽应用领域等。     

Polymeric surfactants for enhanced oil recovery. Part I—critical micelle concentration of some ethoxylated alkylphenol—formaldehyde nonionics

Four low molecular weight nonionic polymeric surfactants were prepared by condensing octyl-, dodecyl-, tetradecyl- and hexadecylphenol with para-formaldehyde, and then reacting the resulting resins with ethylene oxide to obtain products with the desired degree of ethoxylation. The molecular weights of the prepared alkylphenol-formaldehyde resins (prior to ethoxylation) were determined by vapour pressure osmometry. The surface tensions of aqueous solutions of these nonionic polymeric surfactants were determined by using the spinning drop method. Plotting the surface tensions obtained versus the logarithm of concentrations resulted in two lines: the pre-CMC (CMC = critical micelle concentration) line (the linear portion below the CMC value) and the post-CMC line (the linear portion above the CMC value). Least squares regression analysis was performed to get the best equation for each of the two lines. Solving these two equations simultaneously resulted in the value of the CMC and the corresponding surface tension (γ_CMC) for each surfactant of the four polymeric nonionic groups. The CMC values obtained for these polymeric surfactants are of the same order of magnitude obtained for monomeric and other polymeric nonionic surfactants.     

磺酸盐型双基表面活性剂的合成与表面性能

以壬基酚和甲醛为原料,合成了一种新型的磺酸盐型双基表面活性剂(Gemini-A)。利用元素分析、红外光谱确定了Gemini-A的结构。研究了Gemini-A水溶液的润湿性,比较了Gemini-A与传统表面活性剂的增溶能力。试验结果表明,Gemini-A水溶液具有较低的表面张力(33.51 mN/m)和临界胶束浓度(0.141 mmol/L)及良好的润湿性,显示出了较好的表面性能,具有很强的增溶能力,是符合3次采油要求的表面活性剂。     

Molecular thermodynamic model for fluids containing associated molecules

With the statistical mechanical theory for square-well-chain fluids as the basic princi-ples,a molecular thermodynamic model including expressions for the Helmholtz function and thecompressibility factor for associated square-well-chain fluids has been developed.Employment ofthe shield-sticky concept enables the corporation of association bonds between in the model.Good agreement with computer-simulation results for dimer-linear quadrimer systems is obtained.Satisfactory correlation for vapor pressures and saturated liquid volumes of pure substances con-taining associated molecules(such as carboxylic acids,alcohols,amines,water,etc.)with four mo-lecular parameters indicates the applicability of the model.