MIAO Yulong, PEI Xueliang, MO Gaoming, YANG Jianxing, HUANG Qing, HE Liu
(National Engineering Laboratory for Carbon Fiber Preparation Technology, Ningbo Institute of Material Technology and
Engineering, Chinese Academy of Sciences, Ningbo 315201, Zhejiang, China )

Abstract: As one of precursors of fiber-reinforced SiC ceramic matrix composites, liquid hyperbranched polycarbosilane (LHBPCS) has received great attention due to its good fluidity, self-crosslinking, high ceramic yield and the ratio of Si to C in pyrolytic product approaching SiC stoichiometry etc. In a variety of ways of synthesizing LHBPCS, Grignard coupling method has become the focus and direction of research, because its procedures are readily handled, the intermediates needn't be purified, the raw materials are commercially available cheap, and the composition and structure of LHBPCS could be adjusted through changing raw materials and their feed ratio. In this paper,the synthesis of LHBPCS based on Grignard coupling method and the subsequent crosslinking and ceramization processes of LHBPCS were summarized and the prospects of LHBPCS were also proposed.

Key words: silicon carbide ceramics; liquid hyperbranched polycarbosilane; precursor; Grignard coupling method; ceramization