Process for rapid activation of double metal cyanide catalysts
US5844070A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 16, 1997 |
| Grant date | Dec 1, 1998 |
| Priority date | — |
| Expiry date | May 16, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G65/2696
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for activating double metal cyanide catalysts is disclosed. A polyol starter or starter/catalyst mixture is heated under vacuum under conditions effective to achieve improved stripping compared with that which can be achieved through conventional vacuum stripping. Coupling vacuum stripping with inert gas sparging or stripping in the presence of an organic solvent gives a starter/catalyst mixture that activates rapidly in an epoxide polymerization process. Rapid activation makes process start-ups reliable and reduces cycle time. The process gives polyols with lower viscosity, lower polydispersity, and lower unsaturation for better polyurethanes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.