R. Riedel, A. Kienzle, V. Szabó
Jul 1, 1993
Citations
0
Influential Citations
32
Citations
Journal
Journal of Materials Science
Abstract
Polymethylvinylsilanes (PMVS) of the general composition [R2Si]m [RR′Si]n with R=CH3 and R′=CH=CH2 (vinyl) have been synthesized by the dechlorination of dichlordimethylsilane (CH3)2SiCl2 and dichlormethylvinylsilane CH3(CH2=CH) SiCl2 with sodium in toluene. Subsequently, the vinyl groups have been hydroborated by the reaction of the as-synthesized polysilane with various borane adduct compounds such as dimethylsulphide borane (CH3)2S·BH3. The hydroborated polymer was characterized by infrared and 13C-, 1H-, and 11 B-NMR spectroscopy as well as by the measurement of the molecular weight distribution. The pyrolysis of the boron-containing polysilane at 1100 °C in argon results in the formation of X-ray amorphous silicon boron carbide, SixCx+yBz in 63% yield. The crystallization behaviour of the polymer-derived covalent ceramic product at temperatures up to 2200 °C is discussed. The microstructure was characterized by transmission electron microscopy. Analytical results were obtained with the novel electron spectroscopic imaging (ESI) technique.