Perfluorocarbon fluids

The emulsions must not break down in the body to form macroscopic droplets of perfluorocarbon fluid which could cause potentially life-threatening circulation problems. 

Electrochemical fluorination (ECF) is described in Section 6.4.7. for the manufacture of surface-active agents. Coproducts from the ECF of octylsulfonyl fluoride are linear perfluoro-carbons containing from three to eight carbon atoms, while octanoyl fluoride yields a mixture of perfluorocyclic ethers containing mainly perfluoro(2-butyltetrahydrofuran) and perfluoro(2-propylpyran). ECF is also used for the manufacture of specific perfluorocarbon fluids, notably perfluoro(tripropylamine) and perfluoro(tripentylamine), from the corresponding hydrocarbon analogs. 

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. 

Zhu DW, A novel reaction medium Perfluorocarbon fluids, Synthesis, 953-954, 1993. 

Perfluorocarbon fluids, such as the Flutec range (F2 Chemicals Ltd), find many uses in the electronics industry. For instance, the complete immersion of electronic components in a bath of perfluorocarbon fluid can efficiently cool overheated circuits and, by a similar process, the airtight packaging aroimd highly valuable and sensitive equipment can be tested in complete safety for leaks. 

Their pronounced ability to dissolve molecular oxygen in combination with their non-toxicity and complete physiological inertness makes perfluorocarbon fluids attractive for applications as respiratory fluids and as components of artificial blood substitutes [102] (Scheme 4.44). Many perfluorocarbons and perfluorinated amines can dissolve up to 40-50% v/v oxygen at 1 atm and 37 °C. It has been speculated that this unusual oxygen-dissolving capacity is related to the molecular shape and the occurrence of "cavities in perfluorocarbon fluids [103]. 

Perfluorocarbon fluids. A commercially available liquid (b.p. 97°C) is successfully used in 9 different reactions. 

In addition to studying electrode-coating techniques, other processes were considered a means of introducing the perfluorocarbon fluid to the reaction zone. For example, experiments were performed where one chamber in the half-cell apparatus was filled with a perfluorocarbon fluid, such as... 

These results suggest that when the electrocatalytic zone is completely immersed in the perfluorocarbon fluid the diffusion of the reactants and/or products to the catalyst site is impeded by the blocking effect of the additive, which can be described as a flooded system. It is possible that the fluid also interacts with the ionomeric material in the electrocatalytic mixture, decreasing the ability to function as an proton conducting material owing to immiscibility of water with the perfluorocarbon compounds. However, the facility of reaction greatly increases as more of perfluorocarbon exits the system, as shown in Fig. 1.28. These results indicate that the presence of perfluorocarbon fluids have some beneficial effects upon the kinetics of oxygen reduction at Nafion -H-... 

Nonaqueous suspension agents such as paraffin oils have been developed to polymerize polar monomers, such as acrylic acid. The so-called water-in-oil (W/O) suspension polymerization (reversed phase suspension polymerization) comprises an aqueous solution containing the hydrophilic monomer(s) and initiator(s), which are dispersed in a liquid paraffin oil or other nonpolar hydrocarbon media and polymerized. The use of perfluorocarbon fluids has extended the scope of the suspension polymerization method to monomers and initiators that cannot be used, due to their high solubility and reactivity, in conventional suspension media [249]. 

Zhu, D.W. Perfluorocarbon fluids universal suspension polymerization media. Macromolecules 1996, 29, 2813 2817. 

Another possibility for altering a is a complete change of the dispersion medium. Besides water other classes of suitable liquids are alkanes or perfluorocar-bon fluids. By using such materials a drastic decrease in / can be achieved (cf. Table 8.4) when compared to water (/w = 72.8 mN m ). Indeed, it is the state of the art (also in larger-scale technical processes) to use certain petroleum fractions as continuous phases for the polymerization of hydrophilic monomers (so-called inverse heterophase polymerizations) to prepare, for instance flocculants for waste-water treatment or as aids for paper production (14). The large-scale application of perfluorocarbon fluids, however, is restricted... 

Table 8.4. Surface tension values of alkanes and perfluorocarbon fluids (25°C)...

Perfluorocarbon fluids are synthetic liquids that carry dissolved oxygen and carbon dioxide with negligible toxicity, no biological activity, and a short... 

Chambers RD, Edwards AR (1997) Perfluorocarbon fluids as solvent replacements. J Chem Soc Perkin Trans 1 3623-3628. doi 10.1039/A704823H... 

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