PRODUCTION OF SILICON CERAMIC

摘要

PURPOSE:A novel reaction between ammonia and a dihalosilane is effected and the resultant polysilazane is used as a starting material to effect heat treatment under vacuum or in an inert atmosphere to give silicon ceramics easily in high yield. CONSTITUTION:Ammonia is brought into contact with a dihalosilane of the formula: RHSiX2 (R is monovalent hydrocarbon group of 1-6 carbon atoms; X is halogen) to give a polysilazene. The polysilazane is heat-treated at a temperature over 1,200 deg.C in an inert atmosphere or under vacuum to give the desired silicon ceramics. The molecular weight of the polysilazane is preferably more than 10,000. After polysilazane is brought into contact with ammonia and dihalosilane, it is preferably heated at 50-500 deg.C in an inert and anhydrous atmosphere to increase the molecular weight.