Non-thermal plasma polymerization of HFC-134a in a dielectric barrier discharge reactor; Polymer characterization and understanding the mechanism of polymer formation

Summary form only given. The plasma polymerization of HFC-134a (CF
₃
CH
₂
F) has been investigated in a non-thermal plasma dielectric barrier discharge reactor. HFC-134a is a green house gas and it has a global warming potential of 1410 with respect to CO
₂
and 100-year time horizon. Its release is regulated in many countries and its manufacture is likely to be controlled in the near future. A dielectric barrier discharge reactor, constructed from concentric alumina tubes was used for the investigation. The polymer generated from reaction was soluble in tetrahydrofuran solvent which suggests that it is non-crosslinked. The polymer was characterized using various NMR spectroscopic techniques (e.g.,
¹³
C,
¹⁹
F) which reveal that the functional groups in the polymer include CHF, CF
₂
and CF
₃
groups. Based on these data, a detailed reaction mechanism has been developed which is similar but not identical to those available in the open literature. We previously reported the conversion of HFC-143a, the characterization of plasma discharge and the molecular weight of the polymers. This work is focused on a detailed structural analysis of the polymers and a proposed mechanism for their formation.