SYNTHESIS AND POLYMERIZATION OF CYCLOTETRASILAZANES

7-Tetrahydro-1,3,5,7-tetramethylcyclotetrasilazane and etrahydro-1,2,3 ,5,6,7-hexamethylcyclotetrasilazane have been prepared by reaction of 1,3-dichloro-1,3-dihydro-1,3-dimethyldisilazane with ammonia and methy lamine, respectively. The polymerization of these cyclotetrasilazanes by the action of catalytic quantities of potassium hydride and the pyr olysis of the resulting polymers in a stream of argon and in a stream of ammonia is reported. Comparisons are made with the polymers obtaine d by KH treatment of the ammonolysis product of CH3SiHCl2. (C) 1997 Jo hn Wiley & Sons, Ltd.