Preparation of double metal cyanide-catalyzed polyols by continuous addition of starter
US5777177A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 7, 1996 |
| Grant date | Jul 7, 1998 |
| Priority date | — |
| Expiry date | Feb 7, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G2110/0083
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Double metal cyanide-catalyzed polyols are made by an improved process in which a starter is continuously added during polymerization of the epoxide. The process includes a continuously added starter (S.sub.c), and optionally, an initially charged starter (S.sub.i). The continuously added starter comprises at least about 2 equivalent percent of the total starter used. The process enables the use of water and low molecular weight polyol starters in DMC-catalyzed polyol synthesis. In addition, the process gives polyether polyols having reduced levels of high molecular weight polyol tail, which can adversely affect polyurethane foam processing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.