Method for activating double metal cyanide catalysts for the production of polyether carbonate polyols

摘要

The present invention relates to a process for the activation of double metal cyanide (DMC) catalysts with heterocumulenes for the preparation of polyether carbonate polyols by catalytic copolymerization of carbon dioxide (CO₂) with alkylene oxides in the presence of one or more H-functional starter substances, and to a process for the preparation of polyether carbonate polyols from one or more H-functional starter substances, one or more alkylene oxides and carbon dioxide in the presence of a double metal cyanide catalyst, characterized in that(α) under an inert gas atmosphere, under an atmosphere of an inert gas/carbon dioxide mixture or under a pure carbon dioxide atmosphere, at temperatures of from 90 to 150° C., the DMC catalyst is mixed with a heterocumulene and H-functional starter substance,(β) alkylene oxide is added at temperatures of from 100 to 150° C. to the mixture from step (α) under an inert gas atmosphere, under an atmosphere of an inert gas/carbon dioxide mixture or under a pure carbon dioxide atmosphere, and(γ) one or more alkylene oxides and carbon dioxide are metered continuously into the mixture resulting from step (β).