Compositional and sequential analysis of poly(ethylene-tetrafluoroethylene) by pyrolysis-gas chromatography

Abstract Compositional and sequential analysis of PETFE (poly(ethylene (E)-tetrafluoro-ethylene (TFE)-perfluoroalkylethylene (RfCHCH 2 ))) are carried out after optimization of pyrolysis-gas chromatography (Py-GC) experimental conditions. The content of RfCHCH 2 is readily obtained by Py-GC using standard samples whose compositions are known by conventional techniques ( 19 F NMR and total fluorine content analysis). Reproducibility of the determination of each composition by Py-GC stands up to comparison with the conventional techniques. The amount of TFE-TFE sequence in the terpolymer is estimated from seven selected peaks on the pyrogram, so that a rough indication of the TFE E ratio is obtained. Consequently, a quick and easy determination method by Py-GC is established. Furthermore, it is found that crystallinity due to the decrease in the alternating character of the TFE-E sequence may cause the decrease in melting point of the terpolymer.