| 초록 |
Polycarbosilane (PCS) is a well known preceramic polymer as a SiC precursor, which has been used for high temperature structural applications such as fiber, composites. However it was disadvantageous with relatively harsh reaction conditions using an autoclave above 400oC. In this study, PCS was synthesized from polydimethylsilane (PDMS) with the presence of various types of zeolites as catalysts at 350oC for 6hrs and followed by heating to 400oC for additional 6 hrs. The obtained products were mainly fractionated into the soluble solid part and the volatile low molecular weight part by heating at 250oC under a nitrogen atmosphere. Moreover, the soluble solid part was modified by using additives (Polyborazine, Polymethylsilane and SiCBN) to get hybrid precursor. The hybrid precursor PCS were determined by TGA, FT-IR, GPC, NMR, XRD analysis to investigate the effect of the catalyst on characteristics of the polymer. |
