Analysis of pyrolysis products of poly(vinylidene fluoride-co-hexafluoropropylene) by pyrolysis-gas chromatography/mass spectrometry

Poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-co-HFP)) was pyrolyzed and the pyrolysis products were analyzed using gas chromatography/mass spectrometry (GC/MS). Major pyrolysis products were propene, butene, benzene, and cyclohexene derivatives besides VDF and HFP. 2,3,3,3-Tetrafluoropropene (2,3,3,3-TFP) can be formed from the VDF–HFP heterosequence as well as from the VDF head-to-head sequence, while 1,1,3,3-tetrafluoropropene (1,1,3,3-TFP) can be formed from the VDF head-to-tail sequence. 1,3,3,5,5-Pentafluorocyclohexene (PFCH) and benzene derivatives such as 1,3,5-trifluorobenzene (1,3,5-TFB), 1,4-difluorobenzene (DFB), and 1,2,4-trifluorobenzene (1,2,4-TFB) were formed from the VDF homosequences. 1,1,2,3,4,4,4-Heptafluorobutene (HFB) and 3-trifluoromethyl-3,4,4,6,6-pentafluorocyclohexene (FMPFCH) can be formed from the VDF–HFP heterosequences. It is possible to distinguish P(VDF-co-HFP) from other fluorinated polymers using the pyrolysis products formed from the VDF–HFP heterosequences.