| 摘要 |
PURPOSE:To produce the title polymer excellent in moldability and processability and high in a yield of ceramics, by polymeriizng a specified ammonolysis product in the presence of a proton-withdrawing basic catalyst. CONSTITUTION:An ammonolysis product obtained by reacting a mixture comprising 55-80mol% methyldichlorosilane, 10-30mol% methyltrichlorosilane and 5-25mol% dimethyl-chlorosilane with ammonia is polymerized at 0-200 deg.C in a solvent (e.g., toluene) in the presence of a proton-withdrawing basic catalyst (e.g., KH) to obtain an organosilazane of an m.p. of 60-200 deg.C and an intrinsic viscosity of 0.06-0.09. This polymer is molten by heating to 100-300 deg.C and molded. This molding is made infusible by heating to 50-150 deg.C in air or by irradiation with electron beams at 50-200Mrad in a vacuum or a nitrogen gas and fired at 700-2,000 deg.C in a vacuum or a nitrogen gas to obtain ceramics. |
