Abstract:
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).
Abstract:
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).