油脂基表面活性剂研究进展

综述了油脂基表面活性剂的研究进展,重点介绍了阳离子型、阴离子型、非离子型以及两性型油脂基表面活性剂的种类、结构、合成及应用的研究现状,并展望了油脂基表面活性剂的发展前景。     

Hydrolyzable‐emulsifier‐containing polymer latices as dispersants and binders for waterborne carbon black paint

Poly(styrene‐co‐butyl methacrylate) and poly(styrene‐co‐butyl acrylate) latices were prepared by emulsion polymerization with alkali‐hydrolyzable and nonhydrolyzable cationic emulsifiers and were used as a dispersant and binder for waterborne carbon black (CB) paint. CB was dispersed in the latex solutions and then coated on filter paper pretreated with dilute aqueous Na₂CO₃ under mild conditions. The styrene (St)‐rich rigid copolymer latices easily dispersed the CB but fixed a little amount of the pigment on the paper surface. In contrast, the methacrylate‐ and acrylate‐rich soft latices tended to increase the adhesibility on it. We also demonstrated that the hydrolyzable‐emulsifier‐containing latices always had a higher adhesibility than the nonhydrolyzable‐emulsifier‐containing ones. Thus, the hydrolyzable‐emulsifier‐containing latices with an appropriate St content had the highest paintability, rapid adhesion, quick drying, reduced fading, superior fastness, and so on. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3869–3873, 2013     

Evaluation of the influence of polyoxide‐based surfactants on the separation process of model emulsions of asphaltenes using the FTIR‐ATR technique

During extraction of crude oil, water is generally present in the oil. This water‐in‐oil (w/o) mixture undergoes turbulent flow that promotes sheer forces, resulting in the appearance of emulsions. These emulsions can be highly stable due to the presence of compounds with polar characteristics such as asphaltenes, which act as natural emulsifiers and form resistant films at the oil–water interface. Nonionic surfactants based on polyoxides are widely used to prevent the formation or to break down w/o emulsions. To shed more light on the destabilization mechanism of w/o emulsions promoted by these surfactants, in this study the techniques of tensiometry and Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR‐ATR) were applied to study the interface formed by poly(ethylene oxide)‐poly(propylene oxide) (PEO‐PPO) block copolymers and asphaltenic petroleum fractions. Initially, the critical micelle concentration of the copolymers in aqueous solution was determined. The results agreed with those found by tensiometry. The bottle test was used to evaluate the break‐down of the w/o emulsions in the presence of the PEO‐PPO block copolymers, and the results presented good agreement with those obtained by tensiometry and FTIR‐ATR. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

The Effect of Lowering the Surface Free Energy of Water on the Thermodynamic Work of Adhesion

The dispersive and polar force components of surface free energy have been measured for water left in contact with films dried from various emulsion adhesives. The polar component was lowered but the dispersive components were about 28 mJ m^?2 in each case. From these measurements of thermodynamic work of adhesion in the presence of contaminated water have been calculated for adhesive-polystyrene interfaces. An equation has been derived giving the dependence of thermodynamic work of adhesion upon the total surface free energy of water. It shows that the thermodynamic work of adhesion decreases as the surface free energy of water is lowered, but it eventually reaches a minimum and then may increase slightly.     

ADSORPTION OF ETHOXYLATED NONIONIC SURFACTANTS FROM SILOXANE-BASED SOLVENT AND AQUEOUS SYSTEMS: USE OF QCM AND MODEL POLYMERIC SURFACES

Adsorption behavior was quantified with pure ethoxylated nonionic surfactants onto different polymeric surfaces (hydrophilic cotton and hydrophobic polyester) and model hydrophilic gold surface. The polymer materials used for the study were characterized using SEM. The role of ethylene oxide group variation in surfactant-polymer interaction was established using pure surfactant with the same alkyl chain length but varying ethoxylate chain lengths. It was observed that surfactant with more ethylene oxide groups per molecule, being more hydrophilic, interacts favorably with cotton in the hydrophobic siloxane solvent environment. The adsorption of the pure surfactants on model gold surface from hydrophobic solvent and water was also established using the quartz crystal microbalance with dissipation monitoring (QCM-D) system. Effect of ethylene oxide chain length and surfactant concentration on the extent of adsorption was quantified. At the gold-water interface, the plateau adsorption for C₁₂ E₃ (15.9 × 10^?6 mole/m²) is about four times higher than for C₁₂E₈. An opposite trend was observed for adsorption of the surfactants on gold in the hydrophobic D5 environment. Information about thickness, adsorption and desorption kinetics, and structure of adsorbed layer was obtained from the QCM-D frequency-dissipation data. The study is an important contribution towards fundamental understanding of applications involving the use of ethoxylated nonionic surfactants.     

4种新型氟碳表面活性剂

介绍了巨化集团技术中心最新开发的4种氟碳表面活性剂:3-三聚环氧六氟丙烷酰胺基丙基(2-亚硫酸) 乙基二甲基铵、3-三聚环氧六氟丙烷酰胺基丙基甜菜碱、8-3-9氟碳-碳氢柔桥混链双季铵、6-3_9氟碳柔桥混链双季铵。其临界胶束浓度CMC分别为1.14×10-4、1．12×10-3、4．93×10-4、2．78×10-4 mol／L,在临界胶束浓度时表面张力分别为19．0、22．0、20．9、22．7 mN／m,在质量分数0．1％时,表面张力分别为16．4、18．2、19．2、20．4 mN／m。分析了氟碳表面活性剂结构与性能的关系。     

阳离子型双子表面活性剂的合成及表面活性

合成了一种季铵盐型双子表面活性剂Gem in i 12-3-12,采用红外光谱、元素分析和两相滴定法对其结构和纯度进行了分析,测定了不同浓度表面活性剂水溶液的表面张力,并得到临界胶束浓度(CMC)、饱和吸附量(Γm ax)、单分子饱和吸附面积(Am in)。结果表明,Gem in i 12-3-12的收率为77.2%,纯度为98.4%,它与相应的单尾基十二烷基三甲基溴化铵(DTAB)的表面活性相当,但CMC比DTAB低14倍左右。     

改性聚乙烯醇水性憎水剂的研究

研制了一种以聚乙烯醇、2种非离子表面活性剂——Span-20和Tween-20、水溶性缓蚀剂等为原料的水性憎水剂;考察了聚乙烯醇的聚合度和醇解度、2种非离子表面活性剂之间的配比、聚乙烯醇含量、乳化剂含量、水溶性缓蚀剂含量、预处理和后处理工序等因素对憎水剂憎水效果及稳定性的影响。试验结果表明,该憎水剂处理的钢材试样的各项指标优良,有望替代某些溶剂型憎水剂。     

Synthesis and properties of soluble polypyrrole doped with dodecylbenzenesulfonate and combined with polymeric additive poly(ethylene glycol)

Soluble polypyrrole (PPy) samples advanced in electrical conductivity σ were chemically synthesized with dodecylbenzenesulfonate (DBS) sodium salt as a dopant, with poly(ethylene glycol) (PEG) as an additive, and with ammonium persulfate as an oxidant. The PPy–DBS–PEG samples were soluble in organic solvents (N‐methylpyrrolinone and m‐cresol). The greater the molar percentage ratio was of DBS, the greater the solubility was of synthesized PPy composites (PPy–DBS–PEG). The maximum electrical conductivity at room temperature for PPy–DBS–PEG was 1.02 S/cm, which was in fact the true conductivity of 100/10 (mol %) PPy/DBS. The chemical composition and doping level of PPy–DBS–PEG were determined by elemental analysis. The results of Fourier transform infrared spectroscopy were used for the structural characterization of PPy–DBS–PEG. The scanning electron microscopy results showed that the electrical conductivity was related to the morphology of PPy–DBS–PEG. According to thermogravimetric analysis, PPy–DBS–PEG was more thermostable than PPy–DBS. Electron spin resonance measurements showed that the polaron and bipolaron acted as charge carriers of PPy–DBS–PEG. According to the temperature dependence of the electrical conductivity, PPy–DBS–PEG was a semiconductor and followed the three‐dimensional variable‐range hopping model. The improved electrical conductivity apparently resulted from the reduction of the crosslinking and structural defects of the PPy chains. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1170–1175, 2005