Study of Crystallization and Composition on Silicon Oxycarbide (SiOC) and Silicon Boron Oxycarbide (SiBOC) Ceramics Obtained from Alkoxysilanes Precursors

This work deals on the preparation of silicon oxycarbide (SiOC) and silicon boron oxycarbide (SiBOC) ceramics from pyrolysis involving alkoxysilanes with different organic groups. Boron content, organic substituent and annealing time were evaluated on crystallization and composition of resulting ceramics. B-free precursors composed of methyltriethoxysilane (MTES), phenyltriethoxysilane (PTES) and vinyltrimethoxysilane (VTMS) were obtained by the sol-gel method, whilst B-containing precursors were prepared by adding to each alkoxysilane a proper amount of boric acid resulting in B/Si atomic rat...