| 초록 |
Porous SiCN has received a lot of attentions because of its high porosity, large surface area, and excellent thermal stability at extremely high temperature. Polysilazane (PSZ), which is composed of Si and amine in the backbone, is a precursor to form SiCN ceramics by pyrolysis. Since PSZ exhibits polymeric properties before pyrolysis, porous structure can be fabricated more easily than conventional powder ceramic processes. Micro-/meso-sized pores can be generated by removing organic groups during the pyrolysis, and cross-linking of PSZ is very important to maintain the pore structure. In this study, we tried to fabricate hierarchically porous structured SiCN ceramic using phenyl-silsesquiaznae (SSQZ) and freeze-casting process. Due to the branched structure of SSQZ that induced crosslinking during the pyrolysis, the structural stability of the generated pores increased. Glycidyl-POSS and diepoxide was also used to further increase the cross-linking density to prepare porous SiCN. |
