| abstract |
The invention relates to a process for the preparation of polyethercarbonate polyols by addition of alkylene oxides and carbon dioxide to one or more H-functional starter substance (s) in the presence of a double metal cyanide catalyst, characterized in that (α) a suspending agent which does not contain H-functional groups and is selected from one or more compounds selected from the group consisting of aliphatic lactones, aromatic lactones, lactides, cyclic carbonates having at least three optionally substituted methylene groups between the oxygen atoms of the carbonate group , aliphatic cyclic anhydrides and aromatic cyclic anhydrides, in a reactor. (β) optionally adding to the mixture of step (α) a portion of alkylene oxide at temperatures of from 90 to 150 ° C, and then interrupting the addition of the alkylene oxide compound, and (γ) one or more H-functional starter substance (s) are added continuously during the reaction in the reactor. |