Alkanes perfluoro

Perfluoro-w-alkanes Perfluoro-cycloalkanes Perfluoro-w-alkanes Perfluorinated cyclic ethers Perfluorotrialkylamines Perfluoro-w-alkanes Perfluorinated cyclic ethers Perfluorotrialkylamines Homopolymers of hexafluoropropene oxide Photooxidation products of hexafluoropropene or tetrafluoroethene Homopolymers of tetrafluorooxetane... 

Knobler and his co-workers have measured the interaction virial coefficient, for mixtures of n-alkanes and for n-alkane + perfluoro-n-alkane... 

Synonyms C9-C10 alkanes, perfluoro-, sulfonic acid, ammonium salts Definition Ammonium salt of a sulfonated, fluorinated alkane with 9 or 10 carbon atoms in alkyl chain Uses Surfactant in cosmetics... 

Ammonium C9-10 perfluoroalkyl sulfonate Synonyms C9-C10 alkanes, perfluoro-, sulfonic... 

The monofluoromethylene group and difluoromethyl group m 1H perfluoro-alkanes and -cycloalkanes are oxidized at the C-H bond to perfluoroalkyl and perfluorocycloalkyl fluorosulfates by anodic oxidation m fluorosulfonic acid [J, 4] Two modifications of the method are used ox idation by fluorosulfonyl peroxide generated pnor to the reaction [J] (equation 2A) and direct electrolysis m the acid [i, 4] (equabons 2B and 3)... 

The trend of discovering the analytical field of environmental analysis of surfactants by LC-MS is described in detail in Chapters 2.6-2.13 and also reflected by the method collection in Chapter 3.1 (Table 3.1.1), which gives an overview on analytical determinations of surfactants in aqueous matrices. Most methods have focused on high volume surfactants and their metabolites, such as the alkylphenol ethoxylates (APEO, Chapter 2.6), linear alkylbenzene sulfonates (LAS, Chapter 2.10) and alcohol ethoxylates (AE, Chapter 2.9). Surfactants with lower consumption rates such as the cationics (Chapter 2.12) and esterquats (Chapter 2.13) or the fluorinated surfactants perfluoro alkane sulfonates (PFAS) and perfluoro alkane carboxylates (PFAC) used in fire fighting foams (Chapter 2.11) are also covered in this book, but have received less attention. 

The data indicate that as the reduced density of a fluid is increased the cybotatic region becomes more polar/polarizable, with an especially large effect for supercritical NH3. The low it values for Freon-13 at these densities are similar to those of the perfluoro-alkanes ( 5). The values for supercritical C02 and N20 range between those of the perfluoro-alkanes to that of the n-alkanes (n-heptane, etc.) 5). Ammonia gives it values which range from approximately that of n-heptane to that of ethyl acetate or tetrahydrofuran ( 5) over the density range studied. 

The reason why fluorous alkanes are immiscible with normal alkanes possibly stems from their different conformations -alkanes exist in well-known zig-zag conformations, whereas perfluoro-n-alkanes adopt more helical conformations because of the larger van der Waals radius of fluorine (r = 135 pm) as compared to that of hydrogen (r = 120 pm). Molecules of fluorous solvents are also subject to very weak van der Waals interactions due to the low polarizability of the electrons of the CF2 groups. As a... 

Perfluoro tertiary amines (Rf)3N are very inert systems and are more akin to perfluoro-alkanes than amines. They are most directly obtained by electrochemical fluorination [272, 273] (see Chapter 2, Section 111) and, as inert volatile fluids, they are used commercially as evaporation coolants for electronic apparatus. 

Applications of perfluoro-alkane sulfonic and carboxylic acids and their derivatives ... 

Fig. 35 Typical QMS patterns observed from the gaseous species evolved during the SR etching of PTFE at different temperatures. T=RT (top) and 200 °C (bottom), showing similarity to those of perfluoro-n-alkanes (cf., Fig. 36)...

Fig. 36 Typical QMS patterns of perfluoro-n-alkanes. C3F8 (top), C4Fi0 (middle), and the monomer C2F4 (bottom), based on the data given in [72]...

In the vacuum pyrolysis of PTFE, the mass spectrum (Fig. 37, bottom trace) appears nearly identical to that of the monomer (Fig. 36, bottom trace) but different from that of the perfluoro-n-alkanes (Fig. 36, top and middle traces). This agrees with the known fact that pyrolysis generates almost the monomer fragments [36]. 

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