| abstract |
The present invention relates to a method for the production of water-soluble block alkoxylates of a,ß ethylenically unsaturated monocarboxylic or dicarboxylic acids in that the a,ß ethylenically unsaturated monocarboxylic or dicarboxylic acid, or an alkoxylatable derivative thereof, is initially alkoxylated with 1 to 4 mol of propylene oxide per carboxylic acid group, and subsequent to this propoxylation an additional alkoxylation step is carried out with ethylene oxide, or a mixture of alkylene oxides comprising at least 70 mol % ethylene oxide, such that the cloud point defined according to DIN 53917 of the block alkoxylate obtained is at least 75°C, wherein the alkoxylation steps are carried out in presence of DMC catalysts. |