非离子表面活性剂囊泡(niosome)的研究进展——制备、表征及化妆品应用(待续)

在过去的十年里,构建以表面活性剂为基础的囊泡引起了广泛的兴趣和关注,尤其是考虑到其作为纳米药物载体用于改善药物传递方面所具有的潜力.非离子表面活性剂囊泡(niosome)是由非离子表面活性剂、胆固醇或其他两亲分子在水中形成的自组装囊泡状纳米载体,是一种多功能给药体系,其应用范围广泛,包括经皮输送、脑靶向输送等.本综述对...     

Bola型表面活性剂的研究进展

Bola型表面活性剂是以一根疏水链连接2个亲水基团构成的两亲化合物.介绍了Bola型表面活性剂分子的结构与性能,概述了Bola型双亲表面活性剂与传统表面活性剂相比的优点及其在液相中形成的囊泡的特征.重点介绍了各种类型的Bola型双亲表面活性剂的主要合成方法及用途.最后对其研究前景作了展望.     

弱相互作用调控表面活性剂自组装(Ⅲ)——响应性表面活性剂

天然的或合成的两亲分子(表面活性剂)可以自组装形成多尺度的聚集体结构,比如胶束、囊泡、液晶和纤维等。在表面活性剂中引入功能性基团,借助外界环境(比如光、温度、pH、CO2、磁等)的改变可以实现对表面活性剂的聚集方式的调控。本文主要介绍响应性表面活性剂的种类、结构以及环境刺激与响应性能之间的关系。     

表面活性剂在农药加工中的作用

表面活性剂是指那些具有很强表面活性、能使液体的表面张力显著下降的物质。此外表面活性剂还应具有增溶、乳化、润湿、消泡和起泡等应用性质。表面活性剂的分子结构特点是具有不对称性。整个分子可分为两个部分,一部分是亲油的非极性基团,叫作疏水基或亲油基;另一部分是极性基团或亲水基。两部分分处两端,形成不对称结构。     

Bola型表面活性剂2.Bola化合物囊泡

Bola型两亲化合物分子因具有中部是疏水基,两端为亲水基团的特殊结构,可在水中聚集形成单层类脂膜（MLM）和单分子层囊泡（MLM囊泡）。许多单分子层囊泡具有良好的热稳定性。具有两个不同亲水基团的bola化合物可形成内外表面分别由不同亲水基团组成的不对称单分子层囊泡。Bola化合物可以参与到普通两亲化合物所形成的双层类脂膜中并改变膜的稳定性,还可成为连接双层类脂膜内外的电子或离子通道。     

长春新碱纳米缓释新剂型的制备及性能研究

采用非离子表面活性剂在亲水介质中进行自组装,成功制备了双分子层硫酸长春新碱囊泡,并对其制备条件、粒径分布、囊泡形态、包封率及体外释放进行了探究。实验结果表明,通过电子显微镜观察分析,制备的双分子层硫酸长春新碱囊泡呈现规则的球形形态,并具有较为均匀的尺寸分布。紫外分光光度计测定结果显示,囊泡具有较高包封率,能够有效封装药物。体外释放实验显示,双分子层硫酸长春新碱囊泡具有良好的药物缓释性能,释放速率稳定且符合预期缓释效果。研究结果为双分子层硫酸长春新碱囊泡作为药物递送系统的应用提供了有力支持。     

一种双子表面活性剂中间体的合成及表征

双子表面活性剂是由一个连接基在其亲水头基或接近亲水头基处通过化学键将两个传统表面活性剂分子连接在一起而形成的一类新型表面活性剂。由于其特殊的结构,与传统表面活性剂相比,双子表面活性剂具有能高效降低水的表面张力、更低的临界胶束浓度（CMC）、特殊的流变学性质等独特性能,因此在洗涤、杀菌、乳化、分散、防腐以及化妆品、印染、三次采油、基因治疗、有序介孔材料的合成等领域具有较大的应用潜力,     

双子表面活性剂的研究进展

双子表面活性剂是一类分子中含有两个或两个以上亲水亲油基团的新型表面活性剂,由于其结构独特而具有许多优良的性能,如高表面活性、超低表面张力、强协同效应等。总结了双子表面活性剂的合成研究进展,指出该类表面活性剂具有重要的实用价值和广阔的开发前景。     

金属离子诱导形成囊泡研究进展

金属离子诱导表面活性剂分子在水溶液中形成囊泡相,以其特有的作用方式以及潜在的应用价值而引起了广泛的关注。本文对金属离子诱导形成囊泡相的主要研究工作进行了综述,着重介绍了常见金属离子Cu2+,Ca2+,Fe3+与表面活性剂进行配位作用诱导形成囊泡相的研究进展及其作用机理,最后对金属离子诱导形成囊泡相的发展方向作出了展望。     

微生物表面活性剂的生产和潜在生物技术应用(待续)

微生物表面活性剂是两亲分子,其由亲水部分和疏水部分组成。根据其分子量的不同,可将其分为生物乳化剂和生物表面活性剂2大类。微生物表面活性剂根据其化学性质和制备所用的生物体的不同分成很多种类。这些生物分子由包括真菌、细菌和酵母在内的各类微生物所制备。其生产受到底物类型、发酵工艺和微生物菌株的显著影响。由于微生物固有的多功能特性和各种合成能力,微生物表面活性剂在很多工业和生物医学应用中比化学合成的表面活性剂更受青睐,包括生物修复(治理)、采油、作为洗衣粉配方成分,食品和化妆品行业中的乳液稳定剂。作为一种有前途的、具有广泛功能的生物分子,本文对微生物表面活性剂的生产及其在生物技术中的应用进行了综述。     

含氟表面活性剂在农药中的应用

当使用常规助剂(碳-氢链组成)不能发挥药剂的药效时,使用含氟表面活性剂助剂,能起到理想的效果。论述含氟表面活性剂的性能和应用,在10%啶虫脒微乳剂中加入不同助剂,进行了对蚜虫的室内毒力试验。结果表明,使用含氟表面活性剂助剂有明显增效作用;其中含氟表面活性剂OBS助剂增效作用最大(91.70%),有机硅助剂次之(87%)。当含氟表面活性剂OBS与常规助剂JFC复配使用,发挥了最大协同增效作用(96.59%),远胜于含氟表面活性剂OBS助剂单用和与其他含氟表面活性剂助剂复配使用的效果。     

The physicochemical and fire extinguishing performance of aqueous film-forming foams based on a class of short-chain fluorinated surfactants

Aqueous film-forming foams (AFFFs) are an important for fire extinguishing, and their key ingredient is fluorinated surfactant. In recent years, traditional long-chain fluorinated surfactants have been banned by most countries because of their persistence, bio-accumulation and toxicity. Therefore, increased attention has been paid to the research and development of short-chain fluorinated surfactants. As is well known, the introduction of hydrophilic or hydrophobic groups in a surfactant affects its surface activity, and therefore, the fire extinguishing performance of AFFFs. In this work, a series of short-chain fluorosurfactant-based AFFFs with different hydrophobic chain lengths were prepared. The physicochemical performance of mixed systems (fluorinated surfactant plus sodium hexanesulfonate), including surface activity, spreading ability, foam expansion, drainage time, and the fire extinguishing and burn-back performance of AFFFs were studied. The results show that the critical micelle concentration (CMC) and the surface tension (γ_CMC) at the CMC of mixed systems at 25°C are lower than 7.68 mmol/L and 16.51 mN/m, respectively. For mixed systems, the average spreading rate is more than 1.09 cm/s, the foam expansion is over 7.1, and the drainage time is greater than 3.28 min. The fire extinguishing time of AFFFs on fuels is less than 51 s while the burn-back time is more than 15.18 min. The results imply a potential application prospect of the short-chain fluorinated surfactants in AFFFs.     

双尾及多尾氟表面活性剂在有机溶剂中的表面活性研究

拟通过增加油溶性氟表面活性剂分子中碳氟链的数目,从而增大有机溶剂表面吸附层的碳氟链密度,以提高其降低有机溶剂表面张力的能力。合成了2个系列的氟表面活性剂:将全氟辛基磺酰氟与二胺(NH_2(CH_2)nNH_2,n=2,3,6,10)反应,合成以磺酰胺键为连接基、分子中含有2个碳氟链的油溶性氟表面活性剂;通过全氟辛酸与多元醇(乙二醇、1,2-丙二醇、丙三醇和季戊四醇)反应,合成以酯键为连接基、分子中分别含有2,3和4个碳氟链的油溶性氟表面活性剂。研究了这2个系列氟表面活性剂在乙醇、乙酸乙酯、丁酮以及乙醇-乙酸乙酯-丁酮三元混合溶剂中的表面活性,考察了氟表面活性剂分子结构、溶剂种类对表面活性的影响。结果显示,单纯增加碳氟链数目与降低表面张力之间不具有必然的依赖关系,分子整体构型也很重要,同时有机溶剂的种类对氟表面活性剂溶液的表面张力有显著影响。     

Fluorocarbon microemulsions

The microemulsification of various perfluorinated (or almost completely fluorinated) oils with different perfluorinated (or almost completely fluorinated) surfactants with or without cosurfactant is described. Ternary or pseudoternary phase diagrams are discussed. The sizes of the monophasic areas are related to surfactant and cosurfactant nature, weight ratio surfactant/cosurfactant and oil.     

Improving Gas Sequestration by Surfactant‐Alternating‐Gas Injection: A Comparative Evaluation of the Surfactant Type and Concentration

Gas injection into porous subsurface geological formations for geological storage is currently considered the most preferable and practicable means of reducing greenhouse gases due to the huge capacity of deep saline aquifers. Residual trapping of gas plays an important role in immobilization of injected gas into an aquifer. Surfactant‐alternating‐gas (SAG) injection can be used as a mobility control method in gas sequestration and several simulation studies explained different aspects of residual‐gas trapping. However, research in this field is inconclusive and needs more attention to develop a better understanding. In this work, we used 3 different surfactants from different classes at various concentrations to assess gas‐sequestration efficiency using SAG methods in carbonate and sandstone rocks. This work is the first of its kind on the comparative performance of different surfactants for gas sequestration in different rocks. The surfactants were hydrocarbon zwitterionic, fluorinated zwitterionic, and nonionic. It was found that residual‐gas saturation increases by increasing the surfactant concentration. The increase in residual trapping with surfactant concentration also depends on the type of surfactant and rock. In both rock types considered, the best performance was achieved using fluorinated zwitterionic surfactants followed by hydrocarbon zwitterionic surfactants. In addition, a synergetic effect between hydrocarbon and fluorinated surfactants further improves the residual‐gas saturation. The residual‐gas trapping was higher in the tight sample compared to highly permeable samples. This will help in developing an understanding of surfactant optimization and selection for gas sequestration using the SAG method.     

催化调聚法生产全氟碘辛烷的研究与改进

全氟碘代烷是生产含氟整理剂、含氟表面活性剂及其他含氟精细化学品的关键中间体,我国也因国外的垄断而几乎完全依赖进口,严重制约了我国有机氟精细化工的发展。对国外生产全氟碘代烷的方法进行分析,通过对已有催化调聚法的研究,提出了合理化的改进措施和合成工艺。     

氟表面活性剂在造纸和金属表面处理中的应用

概括了氟表面活性剂的性质,根据其某些性质,就其在造纸和金属表面处理中的应用进行了简要的介绍.     

化学驱用特种表面活性剂的文献综述

随着油田开采程度的深入,普通表面活性剂由于其固有的弱点已不能满足在高温高盐条件下提高采收率的要求,于是把目光转向了新型耐温抗盐表面活性剂——特种表面活性剂。化学驱用特种表面活性剂主要包括G em in i型表面活性剂、氟表面活性剂、生物表面活性剂和非离子-阴离子复合型表面活性剂。本文将就特种表面活性剂的研制开发、特性及应用作较详细介绍。     

Novel fluorinated surfactants for enhanced oil recovery in carbonate reservoirs

Novel surfactant‐polymer (SP) formulations containing fluorinated amphoteric surfactant (surfactant‐A) and fluorinated anionic surfactant (surfactant‐B) with partially hydrolyzed polyacrylamide (HPAM) were evaluated for enhanced oil recovery applications in carbonate reservoirs. Thermal stability, rheological properties, interfacial tension, and adsorption on the mineral surface were measured. The effects of the surfactant type, surfactant concentration, temperature, and salinity on the rheological properties of the SP systems were examined. Both surfactants were found to be thermally stable at a high temperature (90 °C). Surfactant‐B decreased the viscosity and the storage modulus of the HPAM. Surfactant‐A had no influence on the rheological properties of the HPAM. Surfactant‐A showed complete solubility and thermal stability in seawater at 90 °C. Only surfactant‐A was used in adsorption, interfacial tension, and core flooding experiments, since surfactant‐B was not completely soluble in seawater and therefore was limited to deionized water. A decrease in oil/water interfacial tension (IFT) of almost one order of magnitude was observed when adding surfactant‐A. However, betaine‐based co‐surfactant reduced the IFT to 10^?3 mN/m. An adsorption isotherm showed that the maximum adsorption of surfactant‐A was 1 mg per g of rock. Core flooding experiments showed 42 % additional oil recovery using 2.5 g/L (2500 ppm) HPAM and 0.001 g/g (0.1 mass%) amphoteric surfactant at 90 °C.     

Assembly properties of the aggregates resulting in the solubilization of phosphatidylcholine bilayers by sodium cholate

The interaction of sodium cholate with phosphatidylcholine liposomes was investigated. Permeability alterations were detected as a change in 5(6)-carboxyfluorescein (CF) released from the interior of vesicles and bilayer solubilization as a decrease in the static light-scattered by liposomes. Free surfactant concentration at subsolubilizing and solubilizing levels showed, respectively, values that were lower than and similar to the surfactant critical micelle concentration, and indicated that permeability alterations and solubilization were determined, respectively, by the action of surfactant monomer and by the formation of mixed micelles. A direct relationship was established in the initial steps [effective surfactant/lipid molar ratio (Re) lower than 0.07] between the growth of vesicles, the leakage of entrapped CF (fluidity of vesicles), and Re. These changes could be correlated with the increasing presence of surfactant molecules in the outer monolayer of vesicles and its saturation. The subsequent increase in Re led to a lower growth of vesicles in coexistence with a similar increase in the CF release. This behavior could be related to a increased rate of flipflop of the sodium cholate molecules, making the inner monolayer also available for the interaction with added surfactant. A direct dependence was also established in the initial solubilization steps (Re values up to 0.6) between the surfactant-phosphatidylcholine aggregate size, the static light-scattering of the system, and Re. In the Re interval 0.36–0.84 mixed vesicles and mixed micelles coexisted.