含活性基团硅氮烷先驱体的裂解

PYROLYSIS OF POLYSILAZANE WITH LATENT FUNCTIONALITES

用TG-GC,IR，元素分析，XRD研究MeSiHCl2与MeSiVi（Vi:-CH=CH2）Cl2共氨解产物的裂解过程．400～800℃在N2中完成裂解，硅氢化反应形成桥键[Si-CH2-CH2-Si，Si-CH（CH3）-Si]和自由基历程导致亚甲基插入形成Si-CH2-Si是裂解产物中富余碳的来源.在NH3中，NH3分子进攻Si-CH3形成低分子产物逸出而脱碳，裂解发生在400～600℃，得到较纯的Si3N4．1400℃以前裂解产物（N2。

TG-GC, IR, elemental analysis and XRD were conbined to trace the Pyrolytic process of polysilazane synthesized by coammonolysis of MeHSiCl2 and Me(CH2=CH)SiCl2 in equimolar ratio. The transformation from organic to inorganic skeleton under N2 was completed betWeen 400 and 800℃, and the Pyrolyzate with excess free carbon was due to the formation of bridge bonds f Si-CH2-CH2-Si and Si-CH(CH3)-Si via hydrosilylation and Si-CH2-Si via radical route. Pyrolysis under NH3 involved the attack Of NH3 to Si-CH3 to remove carbon, leading to lower onset of pyrolytic temperature (400℃)and St3N4 in high purity. The nitrogen introduction into the precursor might attribute the pyrolyzates' retarded cryStallization at higher temperature.