Process for making polyether alcohols having oxyethylene units by polymerization of ethylene carbonate in the presence of double metal cyanide catalysts
US9758619B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 15, 2012 |
| Grant date | Sep 12, 2017 |
| Priority date | — |
| Expiry date | Dec 21, 2032 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G65/2663
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Ethylene carbonate is polymerized by itself or together with another cyclic monomer such as 1,2-propylene oxide in the presence of a double metal cyanide catalyst. Most of the ethylene carbonate adds to the chain to form a terminal carbonate group, which decarboxylates to produce a hydroxyethyl group at the end of the polymer chain. The polymerization of more ethylene carbonate onto the chain end results in the formation of poly(ethyleneoxy) units. Therefore, the process provides a method for making poly(ethyleneoxy) polymers without the need to polymerize ethylene oxide. The process is useful for making polyethers that are useful as water-absorbable polymers, surfactants and as raw materials for polyurethanes. The process is also useful for increasing the primary hydroxyl content of a polyether.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.