摘要
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.
出处
《材料研究学报》
EI
CAS
CSCD
北大核心
1998年第1期64-68,共5页
Chinese Journal of Materials Research