A novel precursor route for the production of Si―B―N ceramic fibers

A novel polymeric precursor to SiBN ceramic fiber was synthesized by reaction of tetramethylaminosilane ((CH3NH)4Si) and trimethylaminoborane ((CH3NH)3B). It was shown that the polymer contains an Si―N―B bridge bond connecting the linear silicon and borazon ring parts. This structure imparts sufficient viscosity for the material to be processed by melt spinning, so that for the first time it was easily spun into green fibers using laboratory scale equipment. SiBN ceramic fibers with diameter 35 μm were obtained after pyrolysis at 1600 °C in an NH3 atmosphere. The thermal decomposition behavior of the polymer during pyrolysis was also investigated.