Cyclosilazanes and borazines: polymer precursors to silicon- and boron-containing ceramics

The chemistry of cyclosilazanes and borazines is a topic of current interes t in view of preceramic polymers which yield on pyrolysis various useful ce ramic materials, e.g, silicon and boron carbide, silicon and boron nitride, and ternary or quaternary mixtures of these materials. These materials are hard and have high oxidative and thermal stability. Other useful propertie s are resistance to corrosion, thermal shock and creep, low electrical cond uctivity and low coefficient of thermal expansion. One of the best applicat ion prospects is the use of the preceramic polymers as protective coating m aterial for carbon fibres, Copyright (C), 2000 John Wiley & Sons, Ltd.