Aminated polysilazane and process for the preparation thereof

A process for the preparation of an amine residue-containing polysilazane having a number average molecular weight of 100-100,000 and having a molecular chain containing a silazane structure represented by the general formula (I) shown below:

• wherein R1 and R2 each stand for hydrogen, a hydrocarbyl group or a hydrocarbyl group-containing silyl group, A stands for a divalent hydrocarbyl group, B stands for an N-hydrocarbyl group-substituted amine residue or a cyclic amine residue and p is 0 or 1 with the proviso that p is 1 when B is an N-hydrocarbyl group-substituted amine residue and that p is 0 when B is a cyclic amine residue, comprising reacting a polysilazane having a molecular chain containing a silazane structure represented by the general formula (III) shown below:
• wherein R1, R2 and R3 each stand for hydrogen, a hydrocarbyl group or a hydrocarbyl group-containing silyl group, with the proviso that at least one of R1 and R3 represents hydrogen,
• with an amine residue-containing monohydroxyl compound represented by the general formula (IV) shown below:
• HO—(A)p—B (IV)
• wherein A, B and p have the same meaning as above, in an inert organic solvent having no active hydrogen.

A process for the preparation of an amine residue-containing polysilazane having a number average molecular weight of 100-100,000 and having a molecular chain containing a silazane structure represented by the general formula (II) shown below:

• wherein R1 and R2 each stand for hydrogen, a hydrocarbyl group or a hydrocarbyl group-containing silyl group, A and A2 each stand for a divalent hydrocarbyl group, B2 stands for a divalent linear amine residue or a divalent cyclic amine residue and r and q are each 0 or 1 with the proviso that r and q are each 1 when B2 is a divalent linear amine residue and that r and q are each 1 or 0 when B is a divalent cyclic amine residue,
• comprising reacting a polysilazane having a molecular chain containing a silazane structure represented by the general formula (III) shown below:
• wherein R1, R2 and R3 each stand for hydrogen, a hydrocarbyl group or a hydrocarbyl group-containing silyl group, with the proviso that at least one of R1 and R3 represents hydrogen, with an amine residue-containing dihydroxyl compound represented by the general formula (V) shown below:
• HO—(A)r—B2—(A2)q—OH (V)
• wherein A, A2, B2, r and q have the same meaning as above, in an inert organic solvent having no active hydrogen.