【摘要】 对甲基乙烯基二氯硅烷(MeViSiCl2)进行氨解形成聚甲基乙烯基硅氮烷(PMVS),进而用二甲基硫醚硼烷(BH3-SMe2)和PMVS进行硼氢化反应,合成出SiBCN陶瓷的前驱体聚硼硅氮烷(polyborosilazane,PBSZ)。Fourier红外光谱分析表明:合成的PBSZ中有C-B-C和Si-N特征吸收峰,分别对应HC-B(CH)-CH和≡Si-NH-基团;11B和29Si的核磁共振分析产物中有BC3,SiN2C2,SiN3C和SiC3N等结构单元,这些光谱结果表明合成的产物为PBSZ。对PBSZ热压成型,在1000℃氩气中热解制备出SiBCN陶瓷体。PBSZ的热重分析表明:氩气中1300℃热解的陶瓷产率为52.6%。陶瓷局部致密,表明用前驱体热解法有望获得致密的SiBCN陶瓷体。更多还原

【Abstract】 Methylvinyldichlorosilane (MeViSiCl2) was ammonolyzed to form polymethylvinylsilazane (PMVS),and then polyboro-silazane (PBSZ) precursor of SiBCN ceramic was synthesized by the reacting between PMVS and borane dimethylsulfide (BH3-SMe2). Fourier transform infrared spectral analysis of PBSZ shows characteristic absorption bands for C—B—C and Si-N bonds corresponding to HC—B(CH)—CH and ≡Si—NH—functional groups,respectively. Solid-state nuclear magnetic resonance (NMR) (11B-NMR,29Si-NMR) analyses show that the PBSZ has the chemical shifts for BC3,SiN2C2,SiN3C and SiC3N units,and it indicates that the synthesized product is PBSZ. The bulk SiBCN ceramics were prepared via pyrolyzing the PBSZ precursor hot-pressing at 1 000 ℃ in Argon. Thermogravimetric analysis of PBSZ shows that the yield of SiBCN ceramic prepared by pyrolyzing the PBSZ precursor at 1 300 ℃ in argon is 52.6%. The ceramic is locally dense,indicating that it is possible to form compact bulk ceramic by the warm-pressing and pyrolysis process.更多还原