In this study, hybrid polymeric networks were prepared by hydrosilylation reaction as precursors to silicon oxycarbide (SiOC) glass. The polymeric networks were prepared from poly(methylsiloxane) (PMS) and divinylbenzene (DVB) in the 80:20 and 20:80 (PMS/DVB) compositions, with or without activated charcoal (AC), which was used as additional carbon source. Following, polymeric precursors were pyrolysed at 1000 °C, under Ar atmosphere, resulting in SiOC glasses. The effectiveness of the hydrosilylation reaction was evaluated by infrared spectroscopy. The degradation reactions and activation energy (Ea) obtained during polymer-to-glass conversion were investigated by thermogravimetric analysis applying Ozawa method for the determination of the Ea. In addition, the influence of the matrix composition and the presence of the C in both degradation processes and structure of the final products were reported. SiOC glasses were characterized by X-ray diffraction and Raman and 29Si nuclear magnetic resonance spectroscopies.
silicon oxycarbide; activation energy; Ozawa method; hybrid polymeric networks; degradation process
