Process for the production of polyisocyanates containing allophanate and isocyanurate groups
US5208334A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 9, 1992 |
| Grant date | May 4, 1993 |
| Priority date | — |
| Expiry date | Jun 9, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G18/792
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The present invention is directed to a process for the production of a polyisocyanate composition having an NCO content of 10 to 47% by weight and a viscosity of less than 2,500 mPa.s, wherein the viscosity is determined from a mixture containing less than 1% by weight of the starting organic diisocyanate, and containing isocyanurate and allophanate groups in a molar ratio of monoisocyanurates to monoallophanates of 10:1 to 1:5 by PA1 a) catalytically trimerizing a portion of the isocyanate groups of an organic diisocyanate having (cyclo)aliphatically bound isocyanate groups PA1 b) adding 0.01 to 0.5 moles, per mole of organic diisocyanate, of a monoalcohol containing 6 to 9 carbon atoms to the organic diisocyanate prior to or during the trimerization reaction of step a) and PA1 c) terminating the trimerization reaction at the desired degree of trimerization by adding a catalyst poison and/or by thermally deactivating the catalyst, wherein said trimerization catalyst is a compound containing aminosilyl groups or a catalyst which is capable of reducing the isocyanate content of a mixture consisting of 1,6-hexamethylene diisocyanate containing less than 10 ppm of carbon dioxide and t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.