Abstract: | The thermal degradation of meta- and para-linked perfluoropolyphenylenes in vacuo and in oxygen has been studied. Rates of breakdown were determined thermogravimetrically and products of breakdown in vacuum analyzed by using a mass spectrometer. The thermal stability in vacuo was comparable with that of polyphenylene, and that in oxygen was rather inferior to that of polytetrafluoroethylene. The higher molecular weight polymers gave as the main volatile degradation products silicon tetrafluoride and carbon dioxide, together with a carbonized residue containing virtually no fluorine. |