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摘要
Polymer precursors for Si(N)OC ceramics have been synthesized by hydrosilylation reaction of polyhydridomethylsiloxane (PHMS) with three different nitrogen containing compounds. The results obtained by combining characterization techniques such as FTIR, C-13- and Si-29-NMR confirm the occurrence of the cross-linking reaction between Si-H and vinyl groups. The structural characterization of the corresponding ceramic phase shows that the type of N-containing compounds strongly influences the pyrolytic transformation as well as the crystallization behavior of the final ceramics. Elemental analysis clearly indicates that N is present in the Si(N) OC matrix and the degree of N retention after pyrolysis is related to the type of N-containing starting compound. XPS data show that N-C bonds are present in the Si(N) OC ceramic samples even if only N-Si bonds are present in the starting N-containing precursors. However, if nitrogen atoms form bonds with sp(2) carbon atoms in the preceramic polymer then a larger fraction of C-N bonds is retained in the final Si(N)OC ceramic.
- 出版日期2015-3-28
