ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract The pyrolysis of polyborosilazane in anhydrous ammonia has been studied up to 1200 °C through the analysis of the gas phase and the characterization of the solid residue by elemental analyses, thermogravimetric analysis, Fourier transform-infrared analysis, X-ray photoelectron spectroscopy, X-ray diffraction and 29Si cross-polarization/magic angle spinning-nuclear magnetic resonance. The pyrolysis mechanism involves four main steps: (1) below 400 °C, an evaporation of residual solvent and reaction with ammonia leading to an increase of nitrogen content; (2) from 400–600 °C, reaction with ammonia leading to an increase of nitrogen content and formation of preceramic polymer-ceramics intermediate solid with a three-dimensional network along with evolution of gaseous species; (3) from 600–800 °C, completion of loss of C-H functionalities and progress of formation of an amorphous ceramic, accompanied by evolution of CH4 and H2; (4) from 800–1200 °C, completion of formation of an amorphous hydrogenated Si-B-O-N solid composed of SiN4−x Ox(x=0,1,2,3) and BN3−y O y (y=0, 1), along with evolution of H2
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00354405
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