PYROLYSIS OF POLYSILAZANE WITH LATENT FUNCTIONALITES

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.