A novel high yield polyborosilazane precursor for SiBNC ceramic fibers.

A novel processable and high yield polyborosilazane (PBSZ) precursor for SiBNC ceramic fibers was synthesized via boron trichloride (BCl 3 ), co-polymerization of trichlorosilane (SiHCl 3 ) and methylamine (MeNH 2 ), followed by trans-amination with NH 3 . The synthesized PBSZ precursor was characterized and the results showed that the polymeric precursor exhibited good melt–processability and green fibers with a diameter of 45 µm could be easily obtained by melt spinning. The green fibers were subsequently pyrolyzed at 1200 °C in nitrogen atmospheres to provide SiBNC ceramic fibers with a cylindrical hollow structure, ca.32 µm in diameter and 720 MPa in tensile strength. The green fibers had an approximately ceramic yield of 78% at 900 °C. [ABSTRACT FROM AUTHOR]