Halophosphazene polymers
US4522797A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 8, 1983 |
| Grant date | Jun 11, 1985 |
| Priority date | — |
| Expiry date | Sep 8, 2003 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B21/0986
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
One or a mixture of compounds of the formula: EQU X--(PX.sub.2 .dbd.N).sub.n --POX.sub.2 wherein X is a halogen atom and n is an integer, usually below about 15 is heated with a suitable phosphorus reactant such as PX.sub.5 ; PX.sub.3 +X.sub.2 ; P+X.sub.2 ; or oligomer of the formula EQU [X--(PX.sub.2 .dbd.N).sub.n --PX.sub.3 ].sup.+ [R].sup.- wherein X is a halogen atom, R is PX.sub.6 or X, and n is an integer usually below about 15; or a mixture of two or more such phosphorus reactants so that a halophosphazene having a --PX.sub.3.sup.+ end group is formed as one of the co-products of the reaction. This co-product is a substance having the general formula EQU [X--(PX.sub.2 .dbd.N).sub.n --PX.sub.3 ].sup.+ [R].sup.- wherein X, R and n are as defined above. The other co-product is phosphoryl trihalide, POX.sub.3. In a second stage the resultant reaction product is heated with at least a stoichiometric amount (preferably, an excess) of a nitrogen source (e.g., NH.sub.3 ; NH.sub.4 Cl; etc.) so that hydrogen halide is evolved and halophosphazene polymer of a suitably high molecular weight is formed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.