Explosion of tetrafluoroethylene during nonisothermal polymerization

The Trifluoromethyl Anion

“…[1] We were able to identify most of the species produced in this decomposition (Figure 4) [10] by comparison of their 19 FNMR spectroscopic parameters with those reported in the literature.A tÀ20 8 8C, the main decomposition product is [(CF 3 CF 2 )C(CF 3 ) 2 ] À , [18] as table tertiary carbanion that is likely produced by aseries of CF 2 insertion, a-and b-F-elimination, and trifluoromethylation reactions, [19] as proposed in Scheme S3 in the Supporting Information. [10] Thermodynamically unstable [20] CF 2 = CF 2 was never detected among the decomposition products and may not be involved in these transformations.…”

Infrared multiphoton dissociation of two perfluorobutenes

“…In these IRMPD experiments direct evidence for a fluorine migration was observed in the loss of CF 2 from octafluoro-2-butene. In addition, at high fluences the TOF spectra for these two molecules begin to share similar characteristics, indicating that the activation barrier for isomerization from octafluoro-1-butene to octafluoro-2-butene is greater than the activation energy for CF 3 loss, but close to the activation energy for CF 2 loss.…”

“…As discussed in the IRMPD experiments on hexafluoropropene, 2 the energy gained from electron pairing upon formation of 1 CFCF 3 can result in a translational energy distribution peaked away from zero. The singlet-triplet splitting for CFCF 3 has been calculated to be 9.2 kcal/mol with the singlet lying lower in energy. 16 If two 1 CFCF 3 species are formed when the double bond is broken, a translational energy distribution peaked at 10 kcal/mol might be reasonable.…”

“…Combustion of tetrafluorethylene without oxygen, produces solid carbon and carbon tetrafluoride. 3 It is unlikely that the formation of carbon tetrafluoride can be attributed to a unimolecular dissociation, since this would involve two fluorine migrations before cleavage of the carbon-carbon ͑C-C͒ bond. One alternative explanation is that the C 2 F 4 pyrolysis products could result from the decomposition of an intermediate species.…”

Explosive-hazard estimates for several fluorine-containing monomers and their mixtures, based on the minimum ignition pressure with a fixed igniter energy

“…Other properties taken into account, tetrafluoroethylene is more hazardous than perfluorobutadien, because the former is characterized by a higher pressure of saturated vapors at a fixed temperature and is prone to spontaneous polymerization on the walls of devices, which can result in an explosion of its vapors under certain conditions [9].…”