Structural characterization and thermal oxidation resistance of silicon oxycarbides produced by polysiloxane pyrolysis

Oxycarbides were produced by pyrolysis of polysiloxanes with different contents of methyl/phenyl groups at 1000 °C under nitrogen atmosphere. The structure of the three silicon oxycarbides was studied by elemental analysis, spectroscopy, and X-ray diffraction. The free carbon phase was concentrated by treatment with hydrofluoric acid. The sp 2 graphene planes merged in sp 3 structures form the free carbon phase. Its content and location in the SiOC network and its structural pattern reflects the sp 2/sp 3 ratio of the source polysiloxanes.