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Conversion of Polymers of Methyl- And Vinylsilane To Sic Ceramics

Published online by Cambridge University Press:  21 February 2011

Frances I. Hurwitz ,
Terrance A. Kacik ,
Xin-Ya Bu ,
John Masnovi ,
Paula J. Heimann  and
Kassahun Beyene
Frances I. Hurwitz
Affiliation:
NASA Lewis Research Center, Cleveland, OH 44135
Terrance A. Kacik
Affiliation:
Cleveland State University, Cleveland, OH 44115
Xin-Ya Bu
Affiliation:
Cleveland State University, Cleveland, OH 44115
John Masnovi
Affiliation:
Cleveland State University, Cleveland, OH 44115
Paula J. Heimann
Affiliation:
Cleveland State University, Cleveland, OH 44115
Kassahun Beyene
Affiliation:
Cleveland State University, Cleveland, OH 44115
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Abstract

Poly(methylsilane) and poly(vinylsilane) were synthesized using a titanocene catalyst, and their pyrolytic conversion to ceramics was followed using a combination of thermal analysis and infrared spectroscopy. The two polymers have distinctly different backbone structures, as determined by 29Si NMR; methylsilane polymerizes to a polysilane, while vinylsilane polymers have a predominately polycarbosilane backbone, with some polysilane structure as well. The pyrolysis path and char yield were dependent primarily on backbone structure, with little influence of polymer molecular weight. The majority of the weight loss on conversion occurs below 650 °C, although bond rearrangement continues to 1400 °C. Poly(vinylsilane) produced a C-rich Si-C ceramic in which the carbon was dispersed on a sufficiently fine level to show resistance to oxidation on heating in air to 1400 °C.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 346: Symposium N – Better Ceramics Through Chemistry VI , 1994 , 623
Copyright
Copyright © Materials Research Society 1998

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References

REFERENCES

1 Masnovi, J. et al. , “Syntheses, structures and properties of polycarbosilanes formed directly by polymerization of alkenylsilanes,” Materials Research Society Symposium (Materials Research Society, San Francisco, 1992), vol. 271, pp. 771-776.Google Scholar
2 Hurwitz, F. I., Heimann, R J., Gyekenyesi, J. Z., Masnovi, J., Bu, X.-Y., “Polymeric routes to silicon carbide and silicon oxycarbide CMC,” Ceram. Eng. Sei. Proc. 12, 1292-1303 (1991).Google Scholar
3 Masnovi, J. et al. , “Polymerization of alkenylsilanes using early transition metal catalysts,” Materials Research Society Symposium (Materials Research Society, San Francisco, 1990), vol. 180, pp. 779-784.Google Scholar
4 Samuel, E., Harrod, J. F., “Synthesis and characterization of a novel bis(cycIopentadienyl)titanium hydride complex,” J. Am. Chem. Soc. 106,1859–1860 (1984).Google Scholar
5 Harrod, J. F., in Inorganic and Organometallic Polymers Zeldin, M., Wynne, K. J., Allcock, H. R., Eds. (American Chemical Society, 1988), vol. 360, pp. 89–100.Google Scholar
6 Harrod, J. F., Yun, S. S., “Silyltitanocene complexes as catalysts for the hydrogénation, isomerization and hydrosilation of olefins,” Organometallics 6,1381–1387 (1987).Google Scholar
7 Corriu, R. J. P., Leclercq, D., Mutin, P. H., Planeix, J.-M., Vioux, A., “Mechanism of pyrolysis of polycarbosilanes: poly(silylethylene) and poly(dimethylsilylethylene),” Organometallics 12,454–462 (1993).Google Scholar
8 Lin-Vien, D., Colthup, N. B., Fateley, W. G., Graselli, J. G., The Handbook of Infrared and Raman Characteristic Frequencies of Organic Molecules. (Academic Press, Boston, 1991).Google Scholar
9 Walsh, R., “Bond dissociation energy values in silicon-containing compounds and some of their implications.,” Ace. Chem. Res. 14, 246–252 (1981).Google Scholar
10 Hasegawa, Y., Okamura, K., “SiC-C composite materials synthesized by pyrolysis of polycarbosilane,” J. Mater. Sei. Lett. 4, 356–358 (1985).Google Scholar
11 Shiina, K., Kumada, M., “Thermal rearrangement of hexamethyldisilane to rimethyl(dimethylsilylmethyl)silane.,” J. Org. Chem. 23, 139 (1958).Google Scholar
12 Zhang, Z.-F. et al. , “Poly(methylsilane)-a high ceramic yield precursor to silicon carbide,” J. Am. Ceram. Soc. 74, 670–673 (1991).Google Scholar