Characterization of fluoroelastomers by various analytical techniques including pyrolysis gas chromatography/mass spectrometry

Fluorocarbon elastomers are specified for a number of applications where excellent high temperature and chemical resistance is required. To ensure that a fluoroelastomer with the required properties for a particular application is used, characterization techniques that allow the positive identification of the elastomer are required. In this paper the characterization of four fluoroelastomer formulations - a vinylidene fluoride/hexafluoropropene (VDF/HFP) dipolymer, a vinylidene fluoride/hexafluoropropene/tetrafluoroethylene terpolymer, and two vinylidene fluoride/perfluoro(methyl vinyl ether)/tetrafluoroethylene (VDF/PMVE/TFE) tetrarpolymers - is described. The characterization techniques included pyrolysis gas chromatography/mass spectrometry (py-GC/MS), Fourier transform infrared (FT-IR) spectrometry, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Py-GC/MS was the only characterization technique that could identify the four formulations unambiguously. The positive identification was based on differences in the pyrolytic degradation products of the flouroelastomer formulations.