Trifluoromethane pyrolysis

The formation of dimeric fluorinated products via heat-induced bond breaking has been more or less restricted to industrial processes. Thus, the pyrolysis of trifluoromethane (1) and chloro-difluoromethane (3) are the two industrial sources for tetrafluoroethene (2), hexafluoropropenc... 

The formation of dimeric fluorinated products via heat-induced bond breaking has been more or less restricted to industrial processes. Thus, the pyrolysis of trifluoromethane (1) and chloro-difluoromethane (3) are the two industrial sources for tetrafluoroethene (2), hexafluoropropenc (4). and their corresponding oligomers and polymers.1-2 Hexafluoropropene (4) is formed as a byproduct in the pyrolysis of chlorodifluoromethane (3) however, a temperature-controlled pyrolysis of 3 has been worked out as a commercial process for the production of 4.3... 

Curie point pyrolysis has been used to carry out quantitative analysis of monomer units in polyhexafluorpropylene-vinylidene fluoride [95]. The polymer composition is calculated from the relative amounts of monomer regenerated and the trifluoromethane produced during pyrolysis. A calibration curve is obtained using samples whose compositions are measured by NMR as standards and a least squares fit calculated. The reproducibility... 

An acetone extract of the polymer is injected into a pyrolysis unit and the pyrolysis products swept into a gas chromatograph. The copolymer composition is calculated from the amount of vinylidine chloride and trifluoromethane produced during pyrolysis. The procedure is calibrated against standard polymers whose composition has been determined by 19p NMR analysis. 

Two calibration plots are made, one of the sum of the relative peak areas for trifluoromethane and hexafluoropropylene produced during pyrolysis against the weight per cent of hexafluoropropylene calculated from 19F NMR data and the other of the relative peak area for vinylidene fluoride produced during pyrolysis against the weight per cent vinylidene fluoride calculated from 19F NMR data. A least square fit was calculated for each calibration plot and the slope and intercept were determined. 

---