A pyrolysis-GC–MS investigation of poly(vinyl phenyl ketone)

The thermal decomposition process and pyrolysis products of poly(vinyl phenyl ketone) (PVPK) were investigated by thermogravimetric analysis (TGA) and on-line pyrolysis-gas chromatography-mass spectrometry (Py-CC-MS). TGA showed a largest weight loss rate around 380 degrees C. Py-GC-MS was used for the qualitative analysis of the pyrolysis products at 350, 500, 600, 700 and 850 degrees C. The major volatile thermal decomposition product was found to be 1-phenyl-2-propenone, which dominated all other volatile species especially under the least severe pyrolysis conditions (<600 degrees C). At higher temperatures a much wider range of pyrolysis products was obtained. The results have been interpreted assuming that primary random chain scission reactions occur followed by typical unzipping mainly producing monomer units; detachment of the side-group occurs only under more severe pyrolysis conditions. PyGC-MS showed to be effective in PVPK detection in ink and paint formulations.