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1.
细小乳状液的制备   总被引:3,自引:0,他引:3  
For preparing O/W miniemulsions containing soybean oil and silicone oil, three methods, phase inversion emulsification, D-phase emulsification, reformed D-phase emulsification were tested by using Brij92, 97, 98 and Tween 80, 85, 60, 20 and Span 80, 60 mixed surfactants. It was found that the O/W miniemulsions of soybean oil and silicone oil can not be formed by phase inversion emulsification method, but can be formed by the two other methods. The results of emulsification showed that if gel emulsion, in which fine oil droplets disperse in continuous phase with high surfactant content, appears during the emulsification process, the O/W miniemulsions can be formed by simply diluting with water.  相似文献   

2.
特征线法在求解非线性液相吸附色谱模型中的应用   总被引:1,自引:0,他引:1  
本文应用特征线法求解非线性液相吸附色谱分离过程模型,论述了特征线法的原理和步骤,讨论了时间步长和空间步长对模型数值解的影响,并用色谱分离甘露醇和山梨醇以及分离蔗糖和还原糖的实验进行验证,用特征线法计算的理论流出曲线与实验流出线吻合较好。本文还分折了模型中各个参数的灵敏度,结果表明:吸附等温方程Q=Ci*/(ai+biCi*)中参数ai比参数bi以及总传质系数ki有更高的灵敏度。  相似文献   

3.
疏水缔合聚合物稳定乳状液的研究*   总被引:2,自引:0,他引:2  
尉云平  孙文彬  孙德军 《化学进展》2009,21(6):1134-1140
本文综述了近年来疏水缔合聚合物稳定乳状液的研究进展。论述了疏水缔合聚合物水溶液的性质,由于其较复杂的分子结构以及其分子主链上疏水基团的缔合作用,使其水溶液增稠的能力比小分子表面活性剂的增稠能力强的多。另外,对疏水缔合聚合物单独稳定乳状液的研究现状进行了介绍,其稳定乳状液的机理与小分子表面活性剂不同。同时讨论了疏水缔合聚合物与表面活性剂的相互作用,此类聚合物可与小分子表面活性剂通过静电和疏水缔合发生强烈的相互作用形成复合体系,并评述了其复配体系稳定乳状液的情况。最后总结了疏水缔合聚合物稳定乳状液的机理。  相似文献   

4.
动态单滴法研究乳状液液膜的稳定性   总被引:2,自引:0,他引:2  
乳状液液膜作为化学分离的一种手段,自七十年代发现以来已有了许多进展,但是如何将其工业化还有许多课题有待于进一步研究.目前,除了乳状液液膜的水静态渗透性质以外,对乳状液液膜的稳定性和溶胀性质的研究主要采用搅拌法.虽然得到较好的规律性,但是搅拌法具有乳状液滴粒径分布广的弱点,对于不同的搅拌方式及条件,乳状液液膜的有效面积不同,对液膜作用的机械强度不同,因此结果会有很大差别.我们自行设计的动态单滴法实验装置,可定量地研究乳状液液膜的溶胀、稳定性及水渗透性质.  相似文献   

5.
乳状液膜处理含铬废水的研究   总被引:6,自引:0,他引:6  
本文对乳状液膜从含铬(VI)废液中提取铬进行了研究,考察了影响铬迁移的几种因素;内外水相pH、表面活性剂、流动载体、添加剂等。结果表明,在合适的操作条件下,当废水中铬的含量在4.8×10^-3mol·L^-1时,经过一级液膜处理,废水中铬的提取率可达99%以上,提余液可以直接排放。  相似文献   

6.
多重乳状液稳定性的研究   总被引:2,自引:1,他引:2  
多重乳状液稳定性的研究刘沛妍,褚莹,吴子生,严忠,康万利(东北师范大学化学系,长春,130024)(大庆石油学院,安达)关键词多重乳状液,示踪法,稳定性W/O型或O/W乳状液的稳定性是研究得比较成熟的课题[1],但对W/O/W型多重(层)乳状液稳定性...  相似文献   

7.
环氧乙烷(EO)环氧丙烷(PO)的共聚物有较好的破乳效果,是目前较理想的破乳剂,已在油田得到应用。这类表面活性剂的特点是只要适当调节EO和PO的比例,就既可用作W/O型乳状液的破乳剂,也可用作O/W型乳状液的破乳剂,但关于后者的研究很少。前已报导加入脂肪醇可显著提高这类表面活性剂对W/O型乳状液的破乳效果。本文继续研究脂肪醇对这类表面活性剂破坏O/W型乳状液的影响。  相似文献   

8.
表面活性剂在胶束电动力学色谱中的应用   总被引:1,自引:0,他引:1  
系统地综述了活性剂在MEKC中的应用,阐述了不同种类表面活性剂的混合表面活性剂胶束体系的特征和应用范围,也对表面活性剂浓度的优化策略作了初步探讨。引用文献56篇。  相似文献   

9.
采用气相色谱质谱电子轰击技术以固体直接进样方法成功地对表面活性剂进行了分离定性,测定了表面活性剂中各个成分的加成环氧乙烷数,定出了各个组分的分子量。  相似文献   

10.
李桂芳  刘昌炎 《色谱》1989,7(3):133-135
]本文从溶质分子间的电荷转移相互作用,讨论了溶质浓度对色谱过程的影响。由于溶质分子间的相互作用,在一定的浓度范围内改变了固定相的表面吸附状态,改变色谱分离效果,两相邻色谱峰的分辨率随溶质浓度而变化。文中以液体色谱为例,着重从理论上进行阐述,力图得出一些清新的概念。这些概念同时也适合于气相色谱,只不过在方程式的表达上略有不同。  相似文献   

11.
Water-in-diesel (W/D) emulsion fuels were prepared through an ultrasonic processor by using high energy emulsification method. Accordingly, the physical and chemical properties were analyzed. A decrease in viscosity was found in the emulsion fuel in contrast to the neat diesel which signifies the enhanced fluidity of the fuel. The emulsion fuel was then used to carry combustion tests in an internal combustion engine. A decrease in exhaust temperature was observed when a high surfactant to water ratio was used, which lead to minimal heat loss. As water is emulsified with diesel, effectiveness of combustion is improved rather than neat diesel fuel. It was also explored that the addition of water-in-diesel is influential in terms of reduction in exhaust gas emission such as carbon dioxide, carbon monoxide, ammonia from the internal combustion engine. Therefore, this type of emulsion fuel would be a useful contribution in the fuel economy, but also in making it environmentally friendly since diesel fuel is now considered one of the leading fuels causing ecological contamination.  相似文献   

12.
以醋酸乙烯酯(VAc)和甲基丙烯酰氧基乙基三甲基氯化铵为主单体,Gemini超支化双子型阳离子表面活性剂和OP-10为复合乳化剂,通过乳液聚合制得一系列阳离子型聚醋酸乙烯酯乳液(1n),考察了VAc的主要杂质乙酸对1n粒径的影响.研究结果表明,乙酸含量增多时,Gemini超支化阳离子表面活性剂的临界胶束浓度和表面张力都...  相似文献   

13.
核壳乳液在电解质作用下的破乳过程   总被引:2,自引:1,他引:1  
顾强  张恺  胡春玲  杨柏 《应用化学》2006,23(2):122-0
核壳乳液在电解质作用下的破乳过程;分光光度计;核壳乳液;电解质;乳液破乳  相似文献   

14.
The diesel engine exhaust gas consists of many hazardous components that need to be reduced. Incorporation of water in fuel restricts the emission of such toxic gases and helps to reduce pollution. The aim of this research work is to develop a water-in-diesel fuel emulsion having maximum stability. Initially, the most suitable surfactant/blend of surfactants has been investigated, which gives the maximum stability to the Water-in-Diesel (W/D) emulsion. It is found that a blend of Span 80 and Tween 80 gives an effective result. The W/D emulsion was prepared by using a high-speed mixing homogenizer and adding a small amount of water into the diesel containing blend of Span 80 and Tween 80. The results show that 10% W/D emulsion having 5% surfactant concentration gives the most desirable emulsion stability. Beyond 10% water concentration, the properties of the W/D emulsion get lowered.  相似文献   

15.
A polymerizable surfactant, sodium dodecyl allyl sulfosuccinate (TREM LF-40; Henkel) and its nonpolymerizable counterpart were used in comparative studies of the emulsion polymerization of vinyl acetate. The conversion-time behavior differed for the two surfactants; the TREM LF-40 showed a decrease in the polymerization rate with increasing concentration while its hydrogenated derivative showed the opposite behavior, the rate increasing with increasing surfactant. Particle size analysis revealed a decreasing particle size with increasing surfactant concentration for both series of reactions. An explanation for the seemingly ambiguous results obtained for the polymerizable surfactant was sought by examining the reactivity of its vinyl group in copolymerization with vinyl acetate and its allylic group in a chain transfer reaction. The results suggest that both the copolymerization and chain transfer reactions can lead to the observed reduction in polymerization rate with increasing TREM LF-40 concentration. © 1992 John Wiley & Sons, Inc.  相似文献   

16.

The emulsion copolymerization of methyl methacrylate and octyl acrylate was studied using a reactive surfactant ammonium sulfate allyloxy nonylphenoxy poly(ethyleneoxy) (10) ether (DNS‐86), and a conventional surfactant sodium dodecylbenzene sulfonate (DBS) with a similar structure as a comparison sample. A series of latex samples have been prepared with two kinds of surfactants, and their properties have been characterized and compared. 1H‐NMR proves that the reactive surfactant has been incorporated into the resulting copolymers. The atomic force microscopy (AFM) proves that the reactive surfactant DNS‐86 migrate to the surface of the latex film to a much less degree than the conventional surfactant DBS. Transmission electron microscopy (TEM) demonstrates that there are some differences in the particle morphologies. The stability and water‐resistance of the latex films prepared by reactive surfactant DNS‐86 are better than those prepared by the conventional surfactant DBS.  相似文献   

17.
Among the variety of possible structures for polymerizable surfactants, it seems clear that the most interesting should be those with the reactive group located in the hydrophobic part of the molecule. We report here a study based on such a surfactant. Its general formula is A set of surfactants has been produced with m varying from 23 to 48 and n = 6 or 12. The compounds have been characterised by 1H-NMR (nuclear magnetic resonance), size exclusion chromatography, surface tension measurements and turbidimetry. These surfactants have been copolymerized with styrene in emulsion polymerization. The coagulum is rather important, except if m is large enough. Although the incorporation of the surfactant in the latex is rather high. Most of the anchored surfactant remains at the surface and is not too buried inside. The particle size decreases with both the amount of surfactant and the length of its hydrophilic part. The use of these polymerizable surfactants leads to an excellent stability of the latex against the addition of electrolytes, and also against freeze-thawing constraints.  相似文献   

18.
Reactive surfactants allow the surfactant molecules to become covalently bound to the particles and thus provide added stability to the colloid particles, longer shelf life, better shear resistance, and polymer particles that can be redispersed. This article reports for the first time the use of a novel addition–fragmentation chain‐transfer reactive surfactant (transurf) in ab initio emulsion polymerizations of methyl methacrylate at 70 °C. It was found that the rate was lowered and average particle diameter nearly doubled when the transurf was used as compared with the SDS experiments (control). In addition the molecular weight distribution was very broad but had a lower Mn than observed in the sodium dodecyl sulfate experiment. Unfortunately because of the formation of many water‐soluble oligomers, the amount of transurf incorporated could not be obtained accurately. However, it was estimated theoretically that only a very small amount of transurf would be consumed, but for an alternative method to increase the incorporation of transurf into the particles, the ratio of monomer to transurf must be kept as low as possible. The best way to achieve this would be to carry the experiments out under starved‐feed conditions. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2813–2820, 2001  相似文献   

19.
建立了气相色谱内标法测定家具白乳胶中苯系物含量的方法。样品中苯系物经甲醇提取、离心,上清液用60 m EN-20色谱柱分离,气相色谱检测,内标法定量。优化条件下苯系物回收率在96.84%~103.86%,相对标准偏差(RSD)为0.79%~2.28%,定量下限2.4~2.9 mg/L。方法操作简单,准确度和精密度较高,是一种检测白乳胶产品中苯系物含量的有效方法。  相似文献   

20.
乳化剂对聚硅氧烷乳液稳定性的影响   总被引:3,自引:0,他引:3  
研究了乳化剂烷基酚聚氧乙烯醚(OP)、烷基聚氧乙烯醚和烷基季铵盐对聚硅氧烷乳液聚合的影响。采用复合乳化剂可以提高乳液稳定性。结果表明:①在以D4、N-β-氨乙基-γ-氨丙基甲基二甲氧基硅烷为原料的乳液聚合中。当非离子型乳化剂烷基聚氧乙烯醚和离子型乳化剂烷基季铵盐复合使用时,二者性能互补,产生协同效应,可使聚合物乳液具有很大的稳定性。②在实验选定的乳化剂中,非离子型烷基聚氧乙烯醚乳化剂用量为80mL(含量为0.05g/mL)、离子型烷基季铵盐乳化剂为60mL(浓度为0.05g/mL)时。其乳液的电解质稳定性、pH稳定性、冻融高温稳定性和离心稳定性等较好。  相似文献   

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