Synthesis and Pyrolysis of Novel Polysilazane to SiBCN Ceramic

Authors

Jongsang Lee, University of Florida
Darryl P. Butt, Boise State UniversityFollow
Ronald H. Baney, University of Florida
Clifford R. Bowers, University of Florida
James S. Tulenko, University of Florida

Document Type

Article

Publication Date

10-1-2005

Abstract

A novel synthesis route was developed to produce exceptionally thermal stable SiBCN-based ceramics. This route turns out to be cheaper, simpler and faster than the conventional route. The SiBCN-based preceramic polymer was synthesized by using three monomers, trichlorosilane (HSiCl₃), boron trichloride (BCl₃), and hexamethydisilazane (HMDZ), at a molar ratio of about 1:1:4. The product becomes an amorphous structure with crosslinked bonds during the elimination of (CH₃)₃SiCl. An intermolecular condensation with the loss of HMDZ occurs in a second stage without the addition of crosslinking agents. In the final pyrolysis stage, hydrogen-rich species such as CH₄ are lost. The chemical structure and composition of the obtained polymer were investigated using IR, MAS-NMR, TGA, DSC, XRD, EA, AA, ICP, and EDS. Through the pyrolysis of preceramic polymers, the mechanisms of the structural and compositional changes at a high temperature were also examined. A preceramic polymer useful for nuclear application can be formed, which provides hydrothermal stability under autoclave test.

Publication Information

Lee, Jongsang; Butt, Darryl P.; Baney, Ronald H.; Bowers, Clifford R.; and Tulenko, James S.. (2005). "Synthesis and Pyrolysis of Novel Polysilazane to SiBCN Ceramic". Journal of Non-Crystalline Solids, 351(37-39), 2995-3005. https://doi.org/10.1016/j.jnoncrysol.2005.06.038