Analysis of polyethylene-particle filled SiCN precursor and the resulting porous ceramics with emphasis on using micro computed tomography

Porous, polymer derived SiCN ceramics are synthesized from a solid polysilazane (PSZMS) and an ultra-high molecular weight polyethylene (PE) as sacrificial filler. Common analytical methods for the investigation of the thermal decomposition processes and the formed (macro) porosities, such as thermogravimetry and mercury porosimetry respectively, were supplemented by micro computed tomography (-CT) measurements. Due to its non-destructive nature, this method enables the comparative analysis of both, the in the first step formed preceramic duromers, to distinguish between the different polymers, as well as the resulting porous ceramics. The via -CT determined values for the two polymer phases after cross-linking are in a good agreement with the used original amounts of PE and PSZMS. In contrast the values for the porosity resulting from the PE filler and for the formed SiCN ceramic after pyrolysis differ in greater extent due to the limiting resolution that can be achiev ed by applying -CT measurements.