Condensation polymerization method for isocyanates
US6653432B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 18, 2002 |
| Grant date | Nov 25, 2003 |
| Priority date | — |
| Expiry date | Jun 18, 2022 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G18/222
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The invention concerns a (cyclo)trimerisation method for isocyanates having at least two isocyanate functions, characterised in that it comprises: a) reacting initial isocyanate monomers having at least two isocyanate functions, optionally in the presence of other monomers reactive with the isocyanate monomers having at least two isocyanate functions at a temperature of at least 20° C., advantageously at least 50° C., and lower than 200° C., advantageously lower than 150° C., in the presence of a compound comprising at least one rare earth alcoholate function; b) stopping the reaction by inactivating the catalyst or its derivative forms in the reaction medium at a transformation rate of at least 2.5% and at most 90% of the initial isocyanate functions; and optionally c) distilling the reaction medium to eliminate the unreacted monomers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.