FLUORINATED ALIPHATIC COMPOUNDS

The extremely nonpolar character of PFCs and very low forces of attraction between PFC molecules account for their special properties. Perfluorocarbons bod only slightly higher than noble gases of similar molecular weight, and their solvent properties are much more like those of argon and krypton than hydrocarbons (2). The physical properties of some PFCs are Hsted in Table 1. 

PFC number Formula CAS Registry Number Molecular weight Boiling point, °C Melting point, °C Liquid density, g/mL at °C Liquid refractive index, at°C Critical temp, °C Critical pressure, MPa  

Flutec number (trademark of Rhc ne-Poulenc, Inc., RTZ Chemicals, ISC Division). Perfluoro-l,3-dimethylcyclohexane. 

The physical properties of hydrofluorocarbons reflect their polar character, and possibly the importance of intermolecular hydrogen bonding (3). Hydrofluorocarbons often bod higher than either their PFC or hydrocarbon counterparts. For example, l-C H F bods at 91.5°C compared with 58°C for n-Q and 69°C for Within the series of fluorinated methanes, the boiling point reaches a maximum for CH2F2, which contains an equal 

Kirk-Othmer Encyclopedia of Chemical Technology (4th Edition) 

There has been increase in the application of these componnds since the synthesis of flnorinated alkanes and related componnds in the 1930s. These include flnorinated hydrocarbons that were formerly nsed as propellants, polymerized tetraflnoroethene, and the polyflnorinated C -Cg carboxyl-ates and snlfonates. All of them are notable for their inertness under normal conditions. Aromatic flnorinated componnds are discnssed in Chapter 9, Part 3. 

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FLUORINECOMPOUNDS,ORGANIC - FLUORINATED ALIPHATIC COMPOUNDS] (Vol 11) -use in cosmetics [COSMETICS] (Vol 7)... 

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