Method for activating double metal cyanide catalysts for producing polyether polyols

摘要

The present invention relates to a process for the activation of double metal cyanide (DMC) catalysts and to a process for the preparation of polyethercarbonate polyols from one or more H-functional starter compounds, one or more alkylene oxides and carbon dioxide in the presence of a double metal cyanide catalyst, characterized in that
(α) (α1) the DMC catalyst and one or more H-functional starter compounds are placed in a reactor,
(α2) an inert gas, an inert gas/carbon dioxide mixture or carbon dioxide is passed through the reactor at a temperature of 50 to 200° C. and at the same time a reduced pressure (absolute) of 10 mbar to 800 mbar is established in the reactor by removal of the inert gas or carbon dioxide,(β) under an atmosphere of inert gas/carbon dioxide mixture or under a pure carbon dioxide atmosphere, alkylene oxide is added to the mixture from step (α) at temperatures of 50 to 200° C., and(γ) one or more alkylene oxides and carbon dioxide are metered into the mixture resulting from step (β).

主权项

1. A process for the preparation of a polyethercarbonate polyol from one or more H-functional starter compounds, one or more alkylene oxides and carbon dioxide in the presence of a double metal cyanide (DMC) catalyst, comprising
(α) (α1) placing the DMC catalyst and one or more H-functional starter compounds in a reactor,
(α2) passing an inert gas, an inert gas/carbon dioxide mixture or carbon dioxide through the reactor at a temperature of 50 to 200° C. and at the same time establishing a reduced pressure (absolute) of 10 mbar to 800 mbar in the reactor by removal of the inert gas or carbon dioxide, to form a mixture, (β) adding, under an atmosphere of inert gas/carbon dioxide mixture or under a carbon dioxide atmosphere, a fraction based on the total amount of alkylene oxides used in steps (β) and (γ), one or more alkylene oxides to the mixture from step (α) at temperatures of 50 to 200° C., and (γ) metering one or more alkylene oxides and carbon dioxide into a mixture resulting from step (β).