The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 26, 1993
Filed:
Nov. 30, 1989
Tilo Vaahs, Kelkheim, DE;
Marcellus Peuckert, Hofheim am Taunus, DE;
Martin Bruck, Hofheim am Taunus, DE;
Hoechst Aktiengesellschaft, Frankfurt am Main, DE;
Abstract
The invention relates to novel polymeric chlorosilazanes, to their preparation, to their processing to form ceramic material containing silicon nitride, and to said material itself. The polymeric chlorosilazanes are prepared by reacting a mixture of oligosilazanes of formula (I) ##STR1## in which n is about 2 to about 12, and oligosilazanes of formula (II), (RSiHNH).sub.m, in which m is about 3 to about 12, with at least one of the chlorosilanes Cl.sub.2 R.sup.2 Si--CH.sup.2 --CH.sub.2 --SiR.sup.2 Cl.sub.2, Cl.sub.3 Si--CH.sub.2 --CH.sub.2 --SiR.sup.3 Cl.sub.2, R.sup.4 SiCl.sup.3 or R.sup.5 SiHCl.sub.2 at 30.degree. C. to 300.degree. C., where R and R.sup.1 to R.sup.5 are C.sub.1 -C.sub.6 alkyl or C.sub.2 -C.sub.6 alkenyl groups which can be identical or different. The polymeric chlorosilazanes according to the invention can be converted into polysilazanes by reaction with ammonia, and these in turn can be pyrolyzed to form ceramic materials containing silicon nitride.