Perfluorocarbons applications

M. Cavazzini, F. Montanari, G. Pozzi, S. Quia, Perfluorocarbon-Soluble Catalysts and Reagents and the Application of FBS (Fluorous Biphase System) to Organic Synthesis , J. Fluorine Chem. 1999, 94,183. 

H.P. Shukla, Application of Perfluorocarbon Emulsions as Fluorine-19 Nuclear Magnetic Resonance Molecular Probes of Cardiac Tissue Oxygen Tension, University of Texas Southwestern Graduate School of Biomedical Sciences, 1994Ph.D.. 

For the use of perfluorocarbon molecules for ophthalmologic applications, see also in this volume the chapter by D. Menz and J.H. Dresp. 

J.U. Bleyl, M. Ragaller, U. Tschoh, M. Regner, M. Hubler, M. Kanzow, O. Vincent, M. Albrecht, Changes in pulmonary function and oxygenation during application of perfluorocarbon vapor in healthy and oleic acid-injured animals, Crit. Care Med. 30 (2002) 1340-1347. 

This very specific ability of perfluorinated compounds to dissolve gases has found an application in oxygen carrier liquids (short-time blood substitutes). A perfluorocarbon dissolves three times more oxygen than the corresponding hydrocarbon, and ten times more than water. This property can be explained by the presence of large cavities in the liquid and by the weak intermolecular interactions of the medium, and not by specific interactions. 

Calibrants are required to calibrate the mass scale of any mass spectrometer, and it is important to find reference compounds that are compatible with a particular ion source. Calibrants commonly used in electron ionization (El) and chemical ionization (Cl), such as perfluorocarbons, are not applicable in the ESI mode. The right calibrants for LC-ESI-MS should (1) not give memory effects (2) not cause source contamination through the introduction of nonvolatile material (3) be applicable in both positive- and negative-ion mode. The main calibrants used or still in use to calibrate ESI-MS can be divided into the following categories polymers, perfluoroalkyl triazines, proteins, alkali metal salt clusters, polyethers, water clusters, and acetate salts. 

Perfluorocarbon fluids possess a unique combination of physical properties which have been exploited in a wide range of applications where the effects provided can justify their relatively high cost. Table 7 lists a selection of illustrative examples. 

Elemental sodium, as well as other alkali metals, reacts with perfluorocarbon polymers by removing fluorine from them. This reaction has a practical application for improving surface wettability and adhesive bonding of perfluorocarbon polymers to other substrates.57... 

Another promising application of S-FFF is the characterization of emulsions and S-FFF is used as the standard technique for emulsion characterization in some laboratories [390]. Manifold emulsions or organelles have been fractionated with S-FFF [75,383,391-396] including perfluorocarbon blood substitutes [391]. 

Another potential application of perfluorocarbons is their use as bulking agents where the volume of conventional solvent is reduced by replacement with a perfluorocarbon. Although the halex reaction is a successful industrial process, there are problems recovering the toxic dipolar aprotic solvents. Chambers [80] has shown that, on a preparative scale, up to 75% of the sulfolane can be replaced in the halex reaction by an equivalent volume of perfluorohydrophenanthrene (b. pt. = 215°C). On cooling the reaction mixture, it is a simple matter to separate off the fluorous solvent at the end of the reaction for recycling. 

In addition to these, various unique manufacturing methods of perfluorocarbon are available, though the industrial applications seem to be difficult. Those who are interested in these techniques should refer to the literatures [21]. 

Perfluorinated membranes are still regarded as the best in the class for PEM fuel cell applications. - These materials are commercially available in various forms from companies such as DuPont, Asahi Glass, Asahi Chemical, 3M, Gore, and Sol-vay. Perfluorosulfonic acid (PFSA) polymers all consist of a perfluorocarbon backbone that has side chains terminated with sulfonated groups. 

As soon as plasma is created, the gas phase is no longer the vapor of the original monomer but becomes a complex mixture of the original monomer, ionized species, excited species of the original monomer, excited species of fragments from the monomer, and gas products that do not participate in polymer formation such as H2 and F2. Perfluorocarbons represent perhaps the most extreme case of ablation competing with polymer formation. The principle found with perfluorocarbons, however, should be applicable to nearly all cases. 

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