Continuous process for the production of low molecular weight polyethers with a DMC catalyst
US9890100B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 14, 2013 |
| Grant date | Feb 13, 2018 |
| Priority date | — |
| Expiry date | Jan 27, 2035 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08G65/2696
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Low molecular weight polyoxyalkylene polyether polyols having a hydroxyl content of from about 3.4 to about 12.1% by weight, and OH numbers of from about 112 to about 400 are produced by a continuous process using a DMC catalyst. In the process of the present invention, oxyalkylation conditions are established in a continuous reactor in the presence of a DMC catalyst; alkylene oxide and a low molecular weight starter are continuously introduced into the continuous reactor; a partially oxyalkylated polyether polyol is recovered from the reactor; and the recovered partially oxyalkylated polyether polyol is allowed to further reactor until the unreacted alkylene oxide content of the mixture is reduced to 0.001% or less by weight. The alkoxylation of the present invention must be carried out a pressure sufficiently high to prevent deactivation of the DMC catalyst. Pressures of from 45 to 55 psia are preferred.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.