Boron/nitrogen preceramic polymers and boron nitride ceramic materials produced therefrom
US5071935A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 6, 1989 |
| Grant date | Dec 10, 1991 |
| Priority date | — |
| Expiry date | Oct 6, 2009 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G79/08
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Organometallic boron/nitrogen polymers, precursors of boron nitride, include recurring structural units of the formulae (I) and (II): ##STR1## wherein X is N-R.sup.3, Y is NR.sup.1 R.sup.2 and Z is N-R, in which R, R.sup.1, R.sup.2 and R.sup.3, which may be identical or different, are each a hydrogen atom, an optionally substituted hydrocarbon radical, or an organosilyl or hydrogenoorganosilyl radical and are prepared by reacting (a) at least one cyclic compound (compound A) containing recurring structural units of the formula (1): ##STR2## wherein A is a halogen atom and R is a hydrogen atom, an optionally substituted hydrocarbon radical, or an organosilyl or hydrogenoorganosilyl radical, with (b) at least one compound including at least one boron atom to which two halogen atoms are directly bonded (compound B), and (c) at least one compound containing at least one NH.sub.2 group compound C); the resulting organometallic polymers are facilely pyrolyzed into boron nitride ceramic materials.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.