Molecular design and synthesis of polyborosilazane precursors for SiBCN ceramics

As important polymeric precursors for siliconboron carbonotide (SiBCN) ceramics applied in high temperature and high oxidation corrosive environments, polyborosilazane precursors with excellent yield of ceramic and process ability have attracted much attention over the last two decades. The recent progress in molecular design and synthesis of polyborosilazane precurosors for SiBCN ceramics is reviewed. Especially the borazine modified polyborosilazane, monofunctional borane modified polyborosilazane on side chain, multi-functional borane based polyborosilazane and boron-cantaining polycarbodiimides are illustrated in view of the molecular design and synthesis, respectively. Accordingly, the new research ideas, such as synthesis of hyperbranched polyborosilazane precursors and preparation of siliconboron carbonotide based micro/nano electromachincal systems (M/NEMS) are proposed based on the progress of polyborosilazane precurosors derived SiBCN ceramics and nanotechnology.