Chemically cross-linked polysilanes as stable polymer precursors for conversion to silicon carbide

Abstract

Cross-linked polysilanes were prepared by the co-polymerization of Me₂SiCl₂ or PhMeSiCl₂ with varying amounts of divinylbenzene (2-15% by weight) using molten sodium as the dehalogenating agent. All the cross-linked polysilanes were stable to air and could be processed thermally for conversion to silicon carbide. Polymers containing from 5-15% of the cross-linking agent underwent a uniform shrinkage during thermal treatment (1500 ° C) to afford β -SiC in good yields. The ceramic was characterized by a variety of techniques including Raman and infrared spectroscopy, powder XRD, as well as Scanning Electron Microscopy (SEM).