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  • 1
    Electronic Resource
    Electronic Resource
    Micellar properties and growth of cationic fluorocarbon surfactant; diethanolheptadecafluoro-2-undecanolmethylammonium chloride (1992)
    Springer
    Colloid & polymer science 270 (1992), S. 927-934 
    Details
    ISSN: 1435-1536
    Keywords: Rod-like micelle ; cationicfluorocarbon surfactant ; dynamiclightscattering ; electricbirefringence ; viscosity
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The micellar properties of a cationic fluorocarbon surfactant, diethanolheptadecafluoro-2-undecanolmethylammonium chloride (DEFUMAC), are studied by surface tension, fluorescence of pyrene-3-carboxaldehyde (PCA), and electric conductivity measurements. These measurements indicate that DEFUMAC solution provides a low surface tension and that its micelles present higher polar conditions under PCA than do cationic hydrocarbon surtactant micelles. Moreover, the micellar elongation induced by increasing concentrations of salt and surfactant concentration is observed by use of dynamic light scattering, transient electric birefringence, and viscosity measurements. The elongation by addition of salt can be explained by a multiple equilibrium description, while the elongation by increasing surfactant concentration is rapid above a particular concentration, viz. second CMC. Consequently, DEFUMAC micelle elongates more rapidly than do corresponding cationic hydrocarbon surfactants with chloride counterion.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00657738
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  • 2
    Electronic Resource
    Electronic Resource
    Phase behavior and dynamic properties in mixed systems of anionic and cationic surfactants: lithium perfluorooctanesulfonate/diethanolheptadecafluoro-2-undecanolmethylammonium chloride (DEFUMAC) and lithium dodecyl sulfate/DEFUMAC aqueous mixtures (1992)
    Springer
    Colloid & polymer science 270 (1992), S. 885-893 
    Details
    ISSN: 1435-1536
    Keywords: Fluorocarbonsurfactant ; mixedsystem ; ion-pairedsurfactant ; P β phase ; lamellarphase
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Two ternary phase diagrams of the cationic perfluorosurfactant diethanolheptadecafluoro-2-undecanolmethylammonium chloride (DEFUMAC) with an anionic perfluorosurfactant lithium perfluorooctanesulfonate (LiFOS) and an anionic hydrocarbon surfactant lithium dodecyl sulfate (LiDS) have been established at 25°C. The total surfactant concentration was less than 20wt%. In a wide mixing region of the LiFOS/DEFUMAC system, a lamellar-type phase,P β, was identified by its texture under a polarization microscope and by its x-ray diffraction pattern. Dispersed fragments ofP β-phase are present in the dilute solutions in which one surfactant was in excess. The anisotropy of electrical conductivity, flow birefringence, dynamic light scattering, and electric briefringence demonstrate that theP β fragments are disk-like with a radius of 0.7 μm. The disk-likeP β particles are transformed by shear into a spherical aggregate ofL α above a critical shear gradient. LiDS/DEFUMAC mixed solution forms dispersed and precipitatedL α in the dominant region. Radius and micropolarity of the dispersedL α aggregates are decreased as the ratio of LiDS:DEFUMAC approaches 1:1. On the basis of x-ray diffraction measurement the structure of precipitatedL α-phase seems to consist of monolayers.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00657733
    Library Location Call Number Volume/Issue/Year Availability
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    Paper (German National Licenses)
    Fulltext
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