Modified polysilazane and process for preparation thereof

A process for the stabilization of an inorganic polysilazane, which comprises reacting (A) an inorganic polysilazane having a number average molecular weight of about 100 to about 100,000 with (B) at least one reactant compound selected from the group consisting of a monoalcohol, an organic monoacid, a monoester, a monoketone, a monoaldehyde, a monomercaptan, and an alkylsilazane and wherein the alkylsilazane is represented by the following general formula:

• ##STR5## wherein groups R independently represent ##STR6## in which groups R' independently represent an alkyl group wherein the reaction is conducted in a basic solvent at a temperature of from 0.degree. C. to the boiling point of the solvent in such a manner that only one polysilazane (A) is present in the polymer after the above reaction, wherein (A) is stabilized by bonding (B) to a side chain or end group of (A) and wherein the resulting polysilazane reaction product is stabilized and has not essentially increased in molecular weight due to cross linkage.