Boron Nitride Precursors ? A Perspective

Research efforts conducted in the Chemistry Division of the Oak Ridge National Laboratory on the preparation of polymeric precursors to boron nitride are reviewed. They evolved from the preparation of powders, which contained significant amounts of residual carbon, derived from the pyrolysis of aminoborane polymers to relatively pure films produced by chemical vapor deposition using polymeric cyanoborane as a single source. Interesting C/B/N films were produced from the pyrolyses of volatile borazine derivatives, and a polymeric borazine intermediate produced denser boron nitride (BN) compact bodies when used as a binder as opposed to bulk BN compressed without a binder. The challenges of producing boron nitride fibers have been defined.