Crystallization of Pyrolyzed Polysilazanes
Roger L. K. Matsumoto, Hercules Incorporated, Research Center, Wilmington, DE 19894.
Polysilazanes are inorganic polymers which convert to a ceramic material when pyrolyzed. Initial pyrolysis results in a solid, amorphous material. Further heating transforms the amorphous structure to a crystalline material. In addition to the Si-N linkages in the polymer backbone, polysilazanes generally contain appreciable amounts of carbon in side groups. Consequently, pyrolysis can result in mixed Si3 N4 - SiC crystalline materials it will be shown that either Si3 N4 or SiC could be selectively crystallized depending upon processing conditions.