Patent ID: 8058388

Claim:
Process for preparing polyethers of the formula (I) R 1 â€”(CHR 2 CHR 3 â€”O) n â€”Hâ€ƒâ€ƒ(I) where n=1 to 12 000, R 1 =a radical comprising at least one carbon atom and R 2 and R 3 are each independently H or a hydrocarbon radical, where the units designated with the index n may be the same or different, by alkoxylating a starter compound which comprises the R 1 radical in the presence of a double metal cyanide catalyst (DMC catalyst) in a loop reactor, characterized in that the alkoxylation is performed in a loop reactor which has an ejector mixing nozzle, in which all substances involved in the reaction or assistants can be added to the circulated reaction mixture, an alkylene oxide or a plurality of different alkylene oxides being metered into the reaction mixture via the ejector mixing nozzle at the same time or at different times wherein an equal total amount of added starter compound and of alkylene oxides, a relatively short sole addition of alkylene oxides carried out after the combined addition leads to a broad molar mass distribution.