| 초록 |
Polysilazane has attracted attentions as a precursor to ceramics, such as silicon carbonitride or silicon nitride. During pyrolyzing polysilazane to ceramics, micro- or meso-sized pores are generated by removing organic groups. However, it is difficult to form macro-sized pores by the simple pyrolysis process. A freeze-casting process can be used for the macro-pores. During the process, solidified solvent is sublimated without causing collapsing pyrolyzed polysilazane and macro-pores can be introduced the pyrolyzed ceramics. In this study, we tried to increase the cross-linking density by adapting silsesquiazane (SSQZ), a branched form of polysilazane, as a precursor to porous ceramics. Water was also used to increase the cross-linking density. As a result, it was possible to form hierarchically porous ceramics having macro-, mseo-, and micro-pores at the same time. |
