Back to results
US 9,169,185 B2Granted
Method for the preparation of polyether polyols
AssigneeBayer Intellectual Property GmbH
InventorsKlaus Lorenz, Joerg Hofmann
Life of this patent
Estimating the term…
Abstract
The invention relates to methods for the preparation of polyether polyols by DMC-catalysed alkylene oxide addition to starter compounds comprising acidic sulfuric acid salts, to the use thereof for the preparation of polyurethanes, and to polyurethanes comprising the polyether polyols according to the invention.
Claims19
A method for the preparation of polyether polyols (1) with a hydroxyl value of 3 mg KOH/g to 150 mg KOH/g, comprising
- (i) preparing a component A) by
- (i-1) forming a crude alkoxylate with an equivalent molar mass of 53Da to 350 Da by reacting a first H-functional starter compound A1.1) with one or more alkylene oxides A1.2) in the presence of a basic catalyst, and then
- (i-2) neutralizing said crude alkoxylate with sulfuric acid, wherein the neutralisation of the alkaline, polymerisation-active centres of said crude alkoxylate is carried out by addition of sulfuric acid such that for from 66 mol % to 100 mol % of the acid used, only the first dissociation step of sulfuric acid is effective for neutralisation of the amount of catalyst present in the crude alkoxylate, and the separation of the salts formed being dispensed with,
- and
- (ii) reacting said component A) with one or more alkylene oxides B1) in the presence of a DMC catalyst B2).
2 more elements
Dependencies are inferred from the claim text.