Thermochemical transformations of polycarbosilane precursors into a ceramic matrix

Autor: N. I. Shvets, A. A. Shimkin, V. T. Minakov, Mikhail I. Buzin, V. S. Papkov, L. Yu. Bad’ina
Rok vydání: 2014
Předmět:
Zdroj: Russian Journal of Applied Chemistry. 87:796-802
ISSN: 1608-3296
1070-4272
DOI: 10.1134/s1070427214060226
Popis: The possibility of preparing polymeric ceramic-forming precursors from polycarbosilane and oligosilazane was examined. Oligosilazane as a component of polycarbosilane formulations acts as a curing agent, ensuring curing at 150–300°C in the absence of oxygen and modifier. Pyrolysis of the cross-linked copolymer in argon yields an inorganic matrix whose yield is 1.3 times higher than that of pyrolyzates of the starting components. The major phase of the ceramic products obtained, according to the results of X-ray diffraction and chemical analyses, is X-ray amorphous silicon carbide. The ceramic obtained is highly resistant to thermal oxidation (up to 1400°C). The composition of the ceramic and the heat resistance and service characteristics of ceramic-matrix composite materials prepared on its basis using the “polymer technology” can be controlled by varying the ratio of the initial oligomers.
Databáze: OpenAIRE