Summary
Cross-linked polycarbosilanes are obtained from the reaction of Cl2MeSiCHCl2 and Mg in tetrahydrofuran, followed by reduction with LiAlH4. Analysis by NMR spectroscopy shows that most polycarbosilane is of the formula [MeSiCH]n.
Zusammenfassung
Durch Reaktion von Cl2MeSiCHCl2 mit Mg in Tetrahydrofuran und anschließende Reduktion mit LiAlH4 erhält man vernetzte Polycarbosilane. NMR-spektroskopische Untersuchungen zeigen, daß das Polycarbosilan überwiegend als [MeSiCH]n vorliegt.
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References
Laine R. M., Babonneau F. (1993) Chem. Mater.5: 260;
Wynne K. J., Rice R. W. (1984) Ann. Rev. Mater. Sci.14: 297;
Peuckert M., Vaahs T., Bruck M. (1990) Adv. Mater.2: 398;
Seyferth D. (1980) In: Zeldin M., Wynne K. J., Allcock H. R. (eds) Inorganic and Organometallic Polymers. American Chemical Society, Washington DC, p 21
Yajima S., Hasegawa Y., Hayashi J., Iimura M. (1978) J. Mater. Sci.13: 2569; Hasegawa Y., Iimura M., Yajima S. J. (1980) Mater. Sci.15: 720; Yajima S. (1980) Am Ceram. Soc. Bull.62: 893.
Kriner W. A. (1964) J. Org. Chem.29: 1601
Seyferth D., Lang H., Michalczyk M. J. unpublished results; Froehling P. E. poster presented at the XXVI Organisilicon Symposium, Indianapolis, April 1993
Whitmarsh C. K., Interrante L. V. (1991) Organometallics10: 1336; Michalczyk, M. J. (1993) U.S. Patent 5,202,405, April 1993
Cross-linking of the pre-ceramic polymer is thought to be necessary to obtain high ceramic yields, see reference 1b.
Michalczyk M. J. (1993) U.S. Patent 5,270,429, December 1993
Van Dyke C. H. (1972) In: MacDiarmid A. G. (ed) The Bond to Halogens and Halogenoids. Marcel Dekker, New York, p 188
In our hands the CH2Cl resonance of Me3SiCH2Cl occurs at 2.74 ppm (CDCl3) and 2.44 ppm (C6D6), and the CHCl2 resonance of Me3SiCHCl2 occurs at 4.80 (C6D6).
Cross-linking in this paper can also refer to cyclic structures within the polycarbosilane.
Doddrell D. M., Pegg D. T., Bendall M. R. (1982) J. Magn. Reson.46: 180
Hasegawa Y., Okamura K. (1986) J. Material Science21: 321; Whitmarsh C. K., Interrante L. V. (1991) J. Organomet. Chem.418, 69; see also reference 5
Related silicon-29 shifts (ppm) are: (H2PhSi)2CH2=−33.48; (H2PhSi)3CH = −30.87; (H3Si)2 CH2=−59.97; (H3Si)3CH=−53.30; Hager R., Steigelmann O., Muller G., Schmidbaur H. (1989) Chem. Ber.122: 2115; (H2SiCH2)3=14.6; (H2SiCCl2)3=−1.1; Fritz G., Braunagle N. (1973) Z. Anorg. Alle. Chem.399: 280
Note: HMe2SiOSiMe2H has a29Si resonance at −4.42 ppm; Helmer B., West R. (1982) Organometallics1: 877
Martel B., Varache M. (1972) J. Organomet. Chem.40: C53; Bertini F., Grasselli P., Zubiani G., Cainelli G. (1970) Tetrahedron26: 1281; Villieras J. (1971) Organometallic Chemistry Reviews A.7: 81
An internal hexadecane standard was used to determine the absolute yields
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Michalczyk, M.J., Davidson, F. Preparation of a cross-linked polycarbosilane and its conversion to silicon carbide ceramics. Monatsh Chem 125, 895–900 (1994). https://doi.org/10.1007/BF00812703
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DOI: https://doi.org/10.1007/BF00812703