Fluorocarbon surfactant

Yamada S and Israelachvili J N 1998 Friction and adhesion hysteresis of fluorocarbon surfactant monolayer-coated surfaces measured with the surface forces apparatus J. Rhys. Chem. B 102 234-44... 

The size and shape of micelles also are affected by fluormation Whereas hydrocarbon surfactants usually form spbencal micelles, linear fluorocarbon surfactants tend to produce larger rodhke speacs [31, 32 This is attnbuted to two inherent charac-tenshcs of the (CF2) chain (1) it adopts a hehcal rather than a linear zigzag conformation [dd 34, 35, 36], and (2) it is much suffer than the (CH2) cham [d5 37, 38] The relatively sbff, helical (CFj) chains thus prefer cylindrical to sphencal packing... 

The high thermal and chemical stability of fluorocarbons, combined with their very weak intermolecular interactions, makes them ideal stationary phases for the separation of a wide variety of organic compounds, including both hydrocarbons and fluorine-containing molecules Fluonnated stationary phases include per-fluoroalkanes, fluorocarbon surfactants, poly(chlorotrifluoroethylene), polyfper-fluoroalkyl) ethers, and other functionalized perfluoro compounds The applications of fluonnated compounds as stationary phases in gas-liquid chroma... 

A foam can be generated by using an inert gas and a fluorocarbon surfactant solution in admixture with an amphoteric or anionic hydrocarbon surfactant solution. A relatively small amount of the fluorocarbon surfactant is operative when mixed with the hydrocarbon surfactant and foamed. The foam has better stability than a foam made with hydrocarbon surfactant alone when in contact with oil [1491]. 

Miscellaneous compounds. Other materials used include FC-171, fluorocarbon surfactant, 3M Industrial Chemical Products Division, St. Paul MN 55144-1000 Byk 306, Bykchemie USA, Wallingford, CT 06492 Polyol (poly-caprolactonetriol a polyester polyol), and Silwet L-7602 (polyalkylene oxide modified polydimethylsiloxane), both from Union Carbide Chemicals and Plastics Co., Inc., Danbury, CT 06817-0001. 

The formulation which performed best contained 1% BAPO/HMPP photoinitiator, 50% acrylate ester of bisphenol A epoxy (Ebecryl 3700), 45% reactive diluent, 5% pigment, and a few drops of the fluorocarbon surfactant FC-171. 

A Study of Mixed Aqueous Solutions of Hydrocarbon and Fluorocarbon Surfactants Using 8-Anilino-l-naphthalenesulfonic Acid Ammonium Salt... 

The miscibility between hydrocarbon and fluorocarbon surfactants was studied by means of a steady-state fluorescence. Three mixed aqueous solutions of surfactants were employed sodium dodecyl sulfate (SDS)-p-t(CF )2CF]2C=C(CFj)0(CH CH O) -CH (NF), hexaoxyethylene-... 

Further, we have observed that ANS is not solubilized into fluorocarbon surfactant micelles, so the miscibility of the fluorocarbon and hydrocarbon surfactants can be studied by using the fluorescence probe, ANS. 

On the other hand, when the fluorocarbon surfactant(NF and LiFOS) concentrations were increased, even at concentrations above their CMC, the fluorescence intensity remained constant and the maximum excitation and emission wavelengths also remained constant. Further, the fluorescence intensity and the maximum excitation and emission wavelength of ANS in the fluorocarbon surfactant solutign were the same as those in water. The C C of NF was about 6x10 mole/1 and that of LiFOS was about 5x10 mole/1. These CMCs were determined by surface tension measurements. ANS was found to be insoluble in fluorocarbon oil, supporting the results showing that ANS is not solubilized into fluorocarbon surfactant. 

Thin films have also been cast from fluorocarbon-surfactant-containing SUVs with bound poly(vinyl alcohol) [436, 437]. Wide angle X-ray diffraction measurements have been interpreted in terms of highly oriented multibilayers and complete substrate coverage by the fluorocarbon surfactants, even at low surfactant-to-poly(vinyl alcohol) ratios (Fig. 70) [437]. 

As noted earlier, one of the agents considered suitable for the extinguishment of petroleum-liquid fires is aqueous film forming foam. This is a liquid concentrate that contains a fluorocarbon surfactant to help float and spread the film across the petroleum-liquid surface and is commonly referred to as A Triple F . AFFF concentrates of 1, 3, or 6 percent are available, all with about... 

AFFF) A fire extinguishing foam based on blended hydrocarbon and fluorocarbon surfactants a rapidly spreading foam used on hydrocarbon fires. See also Fluor-oprotein Foam, Film Forming Fluoroprotein Foam, Alcohol Resisting Aqueous Film Forming Foam. 

There is nothing magical about fluorocarbons or, specifically, the -(CF2) F group [2]. The -(CF2)MF is similar to -(CH2) H in many ways. These include dipole moments and polarizabilities that are related to intermolecular forces and, hence, surface tension. Where they do differ is in size, specifically diameter, and a relative comparison for a typical hydrocarbon and similar fluorocarbon surfactant is shown in Figure 6.54. 

Eastoe J, Paul A, Downer A, Steytler DC, Rumsey E. Effects of fluorocarbon surfactant chain structure on stability of water-in-carbon dioxide microemulsions. Links between aqueous surface tension and microemulsion stability. Langmuir 2002 18 3014-3017. 

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