Journal of Materials Science

, Volume 43, Issue 8, pp 2806–2811

Polymer–ceramic conversion of a highly branched liquid polycarbosilane for SiC-based ceramics


DOI: 10.1007/s10853-008-2539-8

Cite this article as:
Li, H., Zhang, L., Cheng, L. et al. J Mater Sci (2008) 43: 2806. doi:10.1007/s10853-008-2539-8


Liquid polycarbosilane (LPCS) with a highly branched structure was characterized by fourier-transform infrared spectrometry (FT-IR) and 1H, 13C, 29Si nuclear magnetic resonance spectrometry (NMR). The LPCS was then cured and pyrolysized up to 1,600 °C under flowing argon. The structural evolution process was studied by thermogravimetric analysis and differential scanning calorimetry (TG-DSC), FT-IR, and X-ray diffraction (XRD). Hydrosilylation, dehydrocoupling, and polymerization cross-linking reactions between Si–H and C=C groups occurred at low temperatures, which mainly accounted for the high ceramic yield (70%) up to 1,400 °C. The organic groups gradually decomposed and the structure rearranged at high temperatures. The FT-IR analysis revealed that Si–CH2–Si chains, the backbone of original polymer, can be retained up to 1,200 °C. At temperatures higher than 1,200 °C, the Si–CH2–Si chains broke down and crystalline SiC began to form. The final crystalline products were β-SiC and a small amount of carbon.

Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Houbu Li
    • 1
  • Litong Zhang
    • 1
  • Laifei Cheng
    • 1
  • Yiguang Wang
    • 1
  • Zhaoju Yu
    • 2
  • Muhe Huang
    • 2
  • Huibin Tu
    • 2
  • Haiping Xia
    • 2
  1. 1.National Key Laboratory of Thermostructure Composite MaterialsNorthwestern Polytechnical UniversityXi’anChina
  2. 2.Laboratory of Advanced Materials and Department of Materials Science and EngineeringCollege of Chemistry and Chemical Engineering, Xiamen UniversityXiamenChina