| 摘要 |
PURPOSE:To obtain the title copolymer excellent in oxidation resistance and corrosion resistance and useful as a precursor of a silicon carbide (sinter) molding, by mixing a polysilastyrene with a specified metal compound and heating the mixture. CONSTITUTION:Dichlorodimethylsilane is reacted with dichloromethylphenylsilane in the presence of a metallic sodium catalyst in an inert solvent to obtain a polysilastyrene (A) of formula I (wherein R is -CH3, or -C6H5, n is 10-3,000 and X is 0.2-0.9, preferably, 0.3-0.7). Component A is mixed with 0.1-30wt.%, preferably, 1-10wt.%, based on component A, at least one metal compound (B) of formula II (wherein M is Al or B, and R is a lower alkyl or aromatic group), e.g., aluminum triisopropoxide, and the mixture is heated at 200-500 deg.C, preferably, 250-450 deg.C for 5min-10hr in an inert gas atmosphere or in a vacuum to obtain the title copolymer having an MW of 1,000-50,000 and a molar ratio of the silastyrene bonds to the carbosilane bonds of 7-3/3-7.
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