Low-temperature addition of molecular fluorine to unsaturated perfluorohydrocarbons

Article abstract of DOI:10.1007/BF00697069

Calorimetry and ESR spectroscopy were used to study the low-temperature fluorination (77 - 300 K) of unsaturated perfluorohydrocarbons.In the solid phase at 77 - 100 K (glassy or crystalline state) fluorination does not occur.On transition from glassy systems to the overcooled liquid state formation of molecular complexes in which fluorine is attached to the >C=C< bond becomes possible.These complexes are stabilized on crystallization of the system; with a further increase in temperature, efficient addition of molecular fluorine takes place in the crystal phase.However, the addition of fluorine by some chain or carbene mechanism must not be ruled out for such systems.Thus, in the case of hexafluoropropylene trimer, the addition proceeds as a chain reaction producing long-living free radicals at the initial stage.