Influence of fatty acid structure on liquid crystal formation in systems with anionic surfactant,diethyleneglycol ethylether and water

The influence of the fatty acid structure on the formation of transparent gels with lamellar liquid crystal structure, for systems composed of an anionic surfactant, fatty acid, diethyleneglycol ethyl ether and water, was investigated. The influence of the alkyl chain length, for both saturated and unsaturated fatty acids, was considered. Moreover, for a given alkyl chain length, the influence of polyunsaturation was also considered. The results obtained indicate that with saturated fatty acids, it is not possible to form lamellar liquid crystals with the appearance of transparent gels, and that in the case of unsaturated acids, the influence of the alkyl chain length is more important than the degree of unsaturation.     

Optimization of transparent gels for cosmetic compositions

The necessary conditions were established by which several biocompatible ingredients (phosphated oleyl ether 3 mol ethylene oxide as surfactant, oleic acid as the lipophilic ingredient, and diethylene glycol monoethyl ether and 1,2-propanediol as glycols) were combined to formulate transparent gels through dilution with water. This study was carried out at three constant levels of surfactant concentration (5, 10, and 15%), which determined in each case the appropriate ratios between the other three components to give transparent gels. These ratios were expressed as the global ratios between oleic acid and the two glycols together (ranging from 1∶9to 1∶3), whereas the internal ratios between the glycols moved in each case from 1∶0 to 0∶1. The systems with 5% of initial surfactant and a global ratio between oleic acid and the glycols of 1∶7 appeared to be the most effective for minimizing the final surfactant content. They furnished transparent gels at specified levels of water dilution, resulting in final surfactant concentrations in the range of 2–4%. Microscopic observation of the gels through polarized light showed the typical pattern of a lamellar liquid crystal structure. The mild characteristics of these gels, given their low surfactant content and the harmlessness of the other components, in addition to their attractive transparency and the rheological characteristics of plastic fluids make them suitable for application as topical formulations in the cosmetic or pharmaceutical fields.     

聚乙二醇600油酸酯作为气相色谱固定液的研究与应用

本文用聚乙二醇600和油酸合成了聚乙二醇600油酸酯非离子型表面活性剂，精制后作为气相色谱固定液，制备成色谱柱。测定此固定液的最高使用温度、相对极性。对一些混合物组分的分离效果表明了此固定液具有良好的应用性能，是一种新型的气相色谱固定液。     

工艺参数对层状液晶乳液结构的影响

讨论了由聚氧乙烯醚失水山梨醇脂肪酸酯、失水山梨醇脂肪酸酯、直链脂肪醇和挥发性物质组成的层状液晶乳液的制备过程中乳化时原料的加入顺序、乳化时间、冷却时搅拌速度及冷却时间对乳液的形态(脂质体结构,洋葱结构),特别是对乳液颗粒的粒径及粒径分布的影响。结果表明:乳化过程的时间对粒径的分布无明显影响;将水加入到含表面活性剂的油相中有利于形成完整结构的液晶乳液;冷却过程中的搅拌速度及搅拌时间对粒径的影响最大,为了得到较大颗粒为主的粒径分布,较佳冷却条件是搅拌速率在1 500 r/min、冷却60 min;慢速冷却有利于形成层间距较大的层状液晶,快速冷却易形成层间距略小的层状液晶。     

Study on rheology and thermal stability of mixed (nonionic–anionic) surfactant based fracturing fluids

Mixed surfactant systems have gained significant importance in the development of fracturing fluid due to polymorphism of self‐assembly structures that have combined properties of the surfactants in the mixture. In this article, a comparative study on the phase behavior and viscoelastic properties of mixed surfactant based fluids, prepared from Tween 80+NaOA/2‐ethyl hexanol/clove oil/water and Tween 20+NaOA/2‐ethyl hexanol/clove oil/water quaternary system is investigated in details. The viscoelastic surfactant (VES) based fluids prepared from the former system offered superior rheological properties than the latter system. The addition of 0.1% NaOH and 500 ppm ZnO nano‐particles in the VES fluids presented enhanced viscoelastic properties as concluded by static and dynamic rheological tests. Miscibility test indicated the miscibility of the VES fluids with water, unlike in the presence of diesel oil and satisfactory proppant suspension capabilities were exhibited by the developed fluids. © 2016 American Institute of Chemical Engineers AIChE J, 62: 2177–2187, 2016     

氟表面活性剂FN6810与油酸钠复配体系相行为及药物增溶研究

制备并考察了油/FN6810-油酸钠/丁醇/水微乳液体系的相行为及载药性能。采用最大增溶量法绘制了该体系的拟三元相图,筛选出具有较大微乳区面积的最佳处方,进而考察其载药性能及稳定性。结果表明,FN6810与油酸钠的质量比为1∶20,Km=1∶1时微乳体系具有较大的微乳区面积,对油或药物的增溶量较大,载药后粒径变化不大,长时间放置稳定。说明碳氟和碳氢表面活性剂可形成有效的微乳液复配体系,有望在药物制剂中取得应用。     

Complex formation in a ternary system composed of lauroamphoglycinate, oleic acid, and water

The formation of a complex, composed of lauroamphoglycinate (LG), oleic acid (OA) and water, was investigated, and this system was applied to emulsification. The complex was formed in the water-rich area (more than 90% in this system) at a molar ratio of OA to LG from 1 to 3, where two-phase systems of water and the complex existed. The interaction between LG and OA, both in the aqueous solution and at the interface of liquid paraffin dissolving the OA and LG solution, was studied by pH measurements and interfacial tension measurements, respectively. The results implied that LG and OA were linked stoichiometrically, both in aqueous solution and at the interface, and formed complexes. X-ray diffraction patterns and the strong hydrophobicity showed that the equimolar complex composed of LG, OA, and water was a liquid crystal with a reversed hexagonal structure. The reversed hexagonal liquid crystal was capable of solubilizing a certain amount of liquid paraffin in its alkyl group parts while maintaining its hexagonal structure. These results suggest the possibility to prepare a W/O-type emulsion by using the liquid crystal formed by LG, OA, partial liquid paraffin, and water as the continuous phase. The authors could obtain a stable W/O emulsion without coalescence of the water droplets that contained a substantial amount of water (approximately 90%). Furthermore, various types of emulsions, O/W, W/O, W/O/W, could be prepared by changing the ratio of LG and OA.     

Study on the influence of anionic and cationic surfactant on Au-colloid modified electrode function by cyclic voltammetry and electrochemical impedance techniques

The influence of different surfactants on Au-colloid modified electrode function has been investigated by using cyclic voltammetry and electrochemical impedance techniques. Colloidal Au was self-assembled onto the gold electrode through the thiol-groups of 1,6-hexanedithiol (HDT) monolayer. It was found that some HDT molecules stood on the gold electrode and some molecules lay on the electrode by using the quartz crystal microbalance (QCM). A cathodic peak at about 0.486 V (vs. SCE) was observed at the bare gold electrode and the Au-colloid modified electrode. Cyclic voltammetry was used to investigate the influence of different surfactants on the cathodic peak of Au-colloid modified electrode. Electrochemical impedance technique was also used to study the electron transfer ability of the redox probe on Au-colloid modified electrode after being immersed in different surfactants. The results showed that anionic surfactant and cationic surfactant exhibit different behaviors, the reason of which was discussed.     

Influence of anionic concentration and water hardness on foaming properties of a linear alkylbenzene sulfonate

Foam height and foam stability of solutions of a linear alkylbenzene sulfonate (LAS) were measured according to the Ross-Miles test to establish their relationship with ionic concentrations in the solution. The anionic concentration and water hardness were varied alternatively. The results obtained show different behavior for both parameters depending on the concentration of LAS and calcium. However, the results are in line with the proposed theoretical model based on the LAS-calcium precipitation boundary diagram. These tests were aimed at providing a scientific explanation to the complex foaming phenomena. Also, these tests emphasize how essential it is to know the position of the points tested within the LAS-calcium solubility diagram when evaluating the foam properties of an anionic surfactant.     

油酸对壳聚糖/玉米醇溶蛋白复合膜液流变及膜性能的影响

为了提高壳聚糖/玉米醇溶蛋白膜的机械性能，将壳聚糖液与玉米醇溶蛋白液共混，向其中加入0%、15%、30%、45%（w/w）的油酸改性，研究膜液的粒径、zeta电位、静态和动态流变特性；然后，分析油酸添加量对膜阻隔性能，机械性能和相容性的影响。结果表明：添加油酸后，膜液体系粒径增大、分散均匀，添加30%油酸的膜液分散性更好，PDI为0.34，粒径为1307.5nm。随着油酸含量增大，膜液粘度减小，流动指数增大，弹性模量和粘性模量增加。OA-30膜机械性能较好，抗拉强度达到36.37MPa，断裂延伸率达到22.32%。膜的阻隔性增强，水蒸气、氧气透过率分别降低了44.21%和66.52%。复合膜中壳聚糖与玉米醇溶蛋白分子相容性好，表面光滑平整。综上所述，油酸改性改善了壳聚糖/玉米醇溶蛋白复合膜性能。     

Synthesis,Characterization, Evaluation of Interfacial Properties and Antibacterial Activities of Dicarboxylate Anacardic Acid Derivatives from Cashew Nut Shell Liquid of Anacardium occidentale L.

Anacardic acid, 2-hydroxy-6-[(8Z,11Z-pentadeca-8,11,14-trienyl]-benzoic acid, extracted from cashew nut shell liquid (CNSL), has been structurally modified to obtain the 2-(O-carboxymethyl)-6-[(8Z,11Z)-pentadeca-8,11,14-trienyl]-benzoic acid and its disodium carboxylate salt. Our separation method allows to easily obtain anacardic acid, which has been of interest for the fabrication of green products. These methods proposed for the first time to synthesize these derivatives are short and cheap, and with a high yield. The elucidation of its structure was carried out by means of infrared spectroscopy (IR) and nuclear magnetic resonance (NMR) techniques. Interfacial rheology properties of surfactant-air-water and surfactant-heptane-water systems were determined by using a new oscillating spinning drop rheometer apparatus. Physicochemical characterization was performed with a salinity scan in a surfactant-heptane-brine system, obtaining a value of the surfactant characteristic parameter σ = −4.3 for the disodium salt and a critical micellar concentration (cmc) of 0.08 wt%, showing high surface activity. The biological activity of both compounds was determined and measurements of their potential antimicrobial activity against Gram-positive and Gram-negative bacteria were performed, exhibiting high effectiveness, especially for the disodium salt against Gram-positive bacteria.     

Influence of water on phase transition and rheological behavior of cellulose/ionic liquid/water ternary systems

The influence of water content on liquid crystalline (LC) gel formation and the rheological behavior of a ternary microcrystalline cellulose (MCC)/1‐ehtyl‐3‐methylimidazolium acetate (EmimAc)/water system was investigated using polarized optical microscopy (POM) and rheometry. POM indicated that the distinct water content range for forming a fully anisotropic LC gel with 14 wt % MCC was 4–10 wt %. Adding water to the MCC/EmimAc system resulted in enhanced complex viscosity and storage and loss moduli, and ultimately LC gel formation. Comparison of creep compliance vs. time revealed that the system without water showed representative viscoelastic behavior, while the time dependence of creep compliance disappeared as the water content increased, suggesting elastic‐solid behavior. Additionally, hydrogen bonding between cellulose and EmimAc weakened as water content increased, whereas the intra‐ and intermolecular hydrogen bonds of cellulose became stronger because of strong self‐association. This strong bonding caused aggregation, chain entanglement, and self‐supporting LC gel network formation. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44658.     

Effects of Lewis acid catalysts on the esterification kinetics of castor oil with oleic acid

The effects of two Lewis acid catalysts, tin chloride and cobalt chloride, on the kinetics of the esterification reaction between castor oil and oleic acid have been investigated. Uncatalyzed and catalyzed reactions were carried out both in the presence of excess oil and with equivalent amounts of reactants at various temperatures. The reaction, with respect to castor oil concentration, is first-order in all cases, whereas with acid concentration the reaction was observed to change from second-order for the uncatalyzed reaction to first-order for tin chloride-catalyzed and to zero-order for cobalt chloride-catalyzed reactions. The order (with respect to acid) also changed with temperature for the cobalt chloride-catalyzed reaction.     

液膜法提取分离对氨基苯甲酸的研究

由磷酸三丁酯(TBP)、表面活性剂和煤油为油相,氢氧化钠溶液为内水相,含对氨基苯甲酸(PABA)的水溶液为料液(外水相),组成了W/O/W型乳状液膜体系,用乳状液膜法对料液中的PABA进行了分离富集研究。探讨了PA-BA在水中的形态分布及其液膜分离的传质机理,考察了表面活性剂种类、TBP质量分数浓度、外水相pH值和内水相氢氧化钠浓度等因素,对PABA传质分离的影响。结果表明,采用适宜的乳状液膜体系,在最佳的操作条件下,对含PABA浓度为500 mol/L的料液进行分离富集时,仅经一级液膜分离过程,PABA的分离提取率可达99%。     

助乳化剂对化妆品乳液稳定性和液晶性的影响

以硬脂酸蔗糖酯和失水山梨醇硬脂酸酯的复配物（SSE）为主乳化剂，十六／十八醇及甘油为助乳化剂制备含液晶乳液化妆品。通过观察乳液的温度稳定性和液晶性，用三元相图研究助乳化剂含量对此乳液体系液区的影响。实验条件下，用该乳化剂体系可获得较好的液晶化妆品乳液，总之，较高的助乳化剂量有利于乳液的温度稳定性和液晶性，但助乳化剂量较低时经合理配方也能获得稳定的液晶乳液，其中含3％高碳醇和5％甘油的乳液稳定性及液晶性均较好，5％高碳醇和3％甘油的助乳化剂体系不宜采用。     

Electrical behavior of polyurethane derived from polyols synthesized with glycerol,phthalic anhydride,and oleic acid

The direct current (DC) and alternating current (AC) conductivity of polyurethane (PUR) derived from polyols synthesized with glycerol, phthalic anhydride, and oleic acid were investigated in this article. The PUR was prepared by varying the oleic acid content in polyol (28, 40, and 65%) and the NCO/OH ratio of the PUR was varied to 1.2, 1.4, and 1.6. The electrical conduction studied by measuring the dependence of current on the applied field and temperature. Electrical conductivity in PUR was expressed by Arrhenius relations and the activation energies were calculated. Moreover, hyperbolic sine function was used to determine the conduction mechanism in PUR. It's presumed that the conduction mechanism was assisted by ions for the PUR which were contributed by oleic acid due to dissociation of protons and highly polar urethane groups in PUR. Furthermore, the dielectric behaviors of the material have been measured at room temperature in the frequency range of 100 Hz to 40 MHz. The frequency‐dependent conductivity of PUR materials has been analyzed using a Jonscher's power law expression and the plot exhibits the typical behavior of ionic materials, i.e., the DC plateau and the frequency dependent region. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

The effect ofn-decanol on solubilization of water-in-oil microemulsions and stability of lamellar liquid crystals of alkylphenol ethoxylates

Addition of n-decanol at appropriate concentrations is beneficial to increasing the solubilization amount of water in a water-in-oil microemulsion in the system of nonylphenol ethoxylate/olive oil/water, but it destabilized the lamellar liquid crystal and reduced the solubilization of olive oil in the lamellar liquid crystal.     

十二烷基甘油醚羧酸盐阴离子表面活性剂的合成及性能研究

研究了十二烷基甘油醚羧酸盐阴离子表面活性剂的合成条件。首先制备了中间产物十二烷基甘油醚,然后与氯乙酸钠反应制得终产物。考察了反应温度、反应时间、物料摩尔比、氢氧化钠用量及反应方法对反应的影响,得出反应的适宜条件为:浓度为50%的氢氧化钠碱液,n(十二烷基甘油醚)∶n(氯乙酸钠)=1∶1.2,以环己烷作带水剂,100℃下反应6 h,活性物含量达87.6%。测定了该表面活性剂的一系列性能,结果显示,该表面活性剂具有高表面活性,较低的临界胶束浓度和良好的增溶性、稳泡性。