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
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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.
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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