POLYMERIC CHLOROSILAZANE, PREPARATION THEREOF, CERAMIC MATERIAL WHICH CONTAINS SILICON NITRIDE AND CAN BE PRODUCED THEREFROM, AND MANUFACTURE OF SAID CERAMIC MATERIAL

摘要

The polymeric chlorosilazanes are prepared by reacting a mixture of oligosilazanes of the formula (I) …… in which n is from about 2 to about 12, and oligosilazanes of the formula (II) (RSiHNH)m in which m is from about 3 to about 12, with at least one of the chlorosilanes Cl2R<2>Si-CH2-CH2-SiR<2>Cl2, Cl3Si-CH2-CH2-SiR<3>Cl2, R<4>SiCl3 or R<5>SiHCl2 at from 30 DEG C to 300 DEG C, where R and R<1> to R<5> are C1-C6-alkyl or C2-C6-alkenyl groups, which may be identical or different. …The polymeric chlorosilazanes according to the invention can be reacted with ammonia to give polysilazanes, which can themselves be pyrolysed to give silicon nitride-containing ceramic materials.