Abstract: A method is provided for preparing preceramic polymers and and silicious ceramic materials which derive therefrom. The preceramic polymers are polysiloxanes which are synthesized by catalytically activating Si--H bonds in a hydridosiloxane starting material and replacing the activated hydrogen atoms with non-hydrogen substituents. These preceramic polysiloxanes are pyrolyzed in a selected atmosphere to give the desired ceramic product. Ceramic products which may be prepared by this technique include silica, silicon oxynitride, silicon carbide, and metal silicates.

Abstract: A method is provided for preparing preceramic polymers and silicious ceramic materials which derive therefrom. The preceramic polymers are polysiloxanes which are synthesized by catalytically activating Si-H bonds in a hydridosiloxane starting material and replacing the activated hydrogen atoms with non-hydrogen substituents. These preceramic polysiloxanes are pyrolyzed in a selected atmosphere to give the desired ceramic product. Ceramic products which may be prepared by this technique include silica, silicon oxynitride, silicon carbide, and metal silicates.

Abstract: Si-N groups in silazanes (which may be siloxazanes) are cleaved in the presence of a suitable catalyst or one or more reactants containing an Si-H group and an N-H group (in the same molecule or in different molecules) are reacted in the presence of a suitable catalyst. New silazane products result including oligomers and polymers. Suitable catalysts include metal carbonyl complexes and heterogeneous metal catalysts such as platinum on carbon. Immediate products of reaction such as products containing Si-H and N-H groups resulting from Si-N cleavage and Si-N products resulting from Si-H+N-H reactions undergo further reaction, resulting in many cases in a mixture of oligomers or of oligomers and polymers. The initial reactants may be open chain or ring compounds containing Si-N or Si-H+N-H in an open chain or in a ring or as pendant groups.

Abstract: Method of producing polysilazanes from precursors having Si-H, Si-N or Si-Si bonds in the presence of a catalyst effective to activate such bonds. The catalyst may be a metal complex, e.g. a carbonyl cluster, which is soluble in an organic solvent and is homogeneous or it may be a heterogeneous catalyst. Higher polymers, and/or less crosslinking and oligomer formation, and/or greater control over the product and/or faster reactions and/or greater yields result. The polymers are soluble in common organic solvents and/or are solids which can be shaped. The products can be pyrolyzed to silicon nitride or used without pyrolysis.