Microemulsion elastomers

ABA-triblock copolymers bearing polymerizable methacrylate end-groups are covalently crosslinked in the droplet phase of W/O- and O/W-microemulsions. The resulting microemulsion elastomers combine the structure and the phase behavior of microemulsions with solid state properties such as elasticity or stability of shape. These new materials are characterized with the help of conductivity, dynamic-mechanical and dynamic light-scattering investigations. The influence of the chemical crosslinking process on the phase behavior and the dynamics of the underlying microemulsion is discussed.Dedicated to Prof. Dr. Hans-Friedrich Eicke on the occassion of his 65th birthday     

微乳液组成对毛细管微乳液电动色谱的影响

研究了一组电中性芳香族化合物的毛细管微孔液电动色谱分离，考察分离介质微乳液的组成对电动色谱保留时间的影响，实验结果表明，各芳香化俣物的保留时间均随表面活性剂２增加而增长；内相和助表面活性剂对有，无亲水基团入香化合物的保留时间有不同的影响规律，选用微乳液组成为８０ｍｍｏｌ／Ｌ正庚烷－１２０ｍｍｏｌ／ＬＳＤＳ－９００ｍｍｏｌ／Ｌ正丁醇－１０ｍｍｏｌ／Ｌ硼砂，样品在１４ｍｉｎ内达到完全分离，理论板数为３     

O／W微乳液催化苯乙烯聚合动力学研究

Ｏ／Ｗ微乳液催化苯乙烯聚合动力学研究１）郝京诚孙海英汪汉卿２）（中国科学院兰州化学物理研究所兰州７３００００）尤进茂（曲阜师范大学化学系曲阜２７３１６５）关键词微乳液催化苯乙烯聚合动力学分类号Ｏ６４３．１３微乳液作为聚合反应介质，催化单体聚合反应研究...     

Comparison of dodecoxycarbonylvaline microemulsion, solvent-modified micellar and micellar pseudostationary phases for the chiral analysis of pharmaceutical compounds

A direct comparison of dodecoxycarbonylvaline (DDCV) microemulsion, micellar and butanol-modified micellar aggregate systems was performed employing both 2 and 4% DDCV. With respect to either DDCV concentration, use of the micellar system provided the largest elution range, followed by the butanol-modified micellar system and ultimately the microemulsion. Using 2% DDCV, all three aggregate analyses yielded similar values for enantioselectivity, resolution and retention factors that were slightly better using the micellar phase, but efficiencies were consistently better using either the microemulsion or butanol-modified micellar phases. Largely, the microemulsion and butanol-modified micellar phases behaved fairly similar, although use of the butanol-modified micelle provided resolution and efficiency that were slightly better for all but two of the compounds. While reasonable separations were achieved using 2% DDCV, the results using 4% DDCV for the microemulsion system were far superior. Analyses using analogous micellar and butanol-modified micellar aggregates were unstable, making them unsuitable for use at that surfactant concentration.     

HIGH SOLIDS-CONTENT NANOSIZE POLYMER LATEXES MADE BY A MODIFIED EMULSION COPOLYMERIZATION

1.INTRODUCTIONSince1980,agreatdealofresearchinteresthasbeendevotedtomicroemulsionpolymerization[1~10].Amicroemulsionmaybedefinedasthermodynamicallystableandopticallytransparentdispersioncomposedbywater,oilandsurfactant;inmanycasesacosurfactantisrequired.Microemulsionpolymerizationprocesscanyieldstablepolymerlatexeswithparticlesizeofabout10nmto100nm.However,therearetwomajordrawbacks,whichhavelimitedtheapplicationsofmicroemulsionpolymerization:(1)highsurfactantconcentration(upto20wt.%ofthet…     

Effect of Microemulsion Structures on the Hydrolysis of Acetylsalicylic Acid

The hydrolytic kinetics of acetylsalicylic acid in different microemulsion systems have been studied. The results show that the hydrolytic rate is affected by the microemulsion structure and the type of surfactant. The break points of the hydrolytic rate are correspond to the break points in diffusion coefficient and in conductivity that we assign to the W/O, O/W, and bicontinuous structural transitions in the microemulsion single-phase regions.     

Nanotemplate Engineering of Cell Specific Nanoparticles

Abstract

Through nanotechnology, it is now possible to cost‐effectively and reproducibly create and develop useful small particles for applications in the pharmaceutical, medical, chemical, and engineering fields. In the pharmaceutical field, cost‐effective, reproducible, and scalable processes to engineer cell‐ or tissue‐targeted nanoparticles are sought to deliver potent drugs as new therapies. A natural and spontaneous method to engineer nanoparticles has been developed through the use of microemulsions whereby the dispersed phase droplets serve as “nanotemplates” to directly form stable nanoparticles. The present review will serve to provide an overview of the challenges and opportunities in developing ideal nanoparticulate carrier systems and the use of microemulsion precursors to engineer nanoparticles. An overview will be presented on our work in targeting surface‐modified nanoparticles to (1) dendritic cells for potential new types of genetic and subunit protein vaccines, and (2) solid tumors for potential neutron capture therapy (NCT) using gadolinium.     

Micro‐ and Nanoemulsions in Cosmetic and Pharmaceutical Products

This article presents a model of droplet disruption in an ultrasonic field. It describes the experiments with preparing fine emulsions in the ultrasonic field.     

阴离子型微乳液对火焰原子吸收法测铅增敏作用的研究与应用

研究了在空气－乙炔火焰中，阴离子型表面活性剂十二烷基硫酸钠（ＳＤＳ）组成的微乳液对铅原子化行为的影响。结果表明：在ＳＤＳ组成的微乳液存在下，铅的灵敏度提高了近６０％，比ＳＤＳ胶束存在下灵敏度也提高了２０％。方法用于黄铅和工业废水中铅的测定，结果令人满意。     

Self-assembling properties of glycolipid biosurfactants and their potential applications

Biosurfactants (BS) produced by a variety of microorganisms show unique properties (e.g. mild production conditions, multi-functionality, higher environmental compatibility) compared to their chemical counterparts. The numerous advantages of BS have prompted applications not only in the food, cosmetic, and pharmaceutical industries but in environmental protection and energy-saving technology as well. Among BS, “Glycolipid type” BS are the most promising, due to high productivity from renewable resources and versatile interfacial and biochemical properties. Mannosylerythritol lipids (MELs), which are glycolipid BS produced by yeast strains of the genus Pseudozyma, not only exhibit excellent surface activities but also self-assemble to form different lyotropic liquid crystalline phases such as sponge (L₃), bicontinuous cubic (V₂) or lammellar (L_α). They also show induction of cell-differentiation against human leukemia cells, and high binding affinity towards lectins and immunoglobulins. Recently, the cationic liposome bearing MELs has been demonstrated to increase dramatically the efficiency of gene transfection into mammalian cells. These features of BS should broaden the applications in new advanced technologies. The current status of R&D on glycolipid BS, especially their functions and potential applications, is discussed.