A new SiC precursor with high ceramic yield: Synthesis and characterization of CHxMeSiH2-containing poly(methylsilane-carbosilane)

摘要

A new poly(methylsilane-carbosilane) (PMSCS) for silicon carbide precursor was prepared using Wurtz-type copolymerization of methyldichlorosilane (MeHSiCl2), chloromethyldichloromethylsilane (ClCH2MeSiCl2), and (dichloromethyl)methylsilane (Cl2CHMeSiH2), with (chloromethyl)methylsilane (ClCH2MeSiH2) or trimethylchlorosilane (Me3SiCl) as terminated reagent. The ceramic yield of PMSCS was markedly increased by introduction of Cl2CHMeSiH2 comonomer and capped with ClCH2MeSiH2. The H2MeSiCH2-capped PMSCS with (sic)CHMeSiH2 structure unit in main chain produced SiC ceramic with 1.21 of C/Si atomic ratio in a ceramic yield of 78 wt % upon pyrolyzed at 1000 degrees C. The excellent pyrolytic properties, combining with its economical preparation, good storage stability in air, and favorable processabilty, make the CHxMeSiH2-containing PMSCS a new cost-effective SiC ceramic precursor. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47618.