A method for producing polyether carbonate polyols via the following steps: (i) accumulating alkylene oxide and carbon dioxide on a H-functional starter substance in the presence of a double metal cyanide catalyst or a metal complex catalyst based on the metals zinc and/or cobalt, wherein a reaction mixture containing the polyether carbonate polyol is obtained; and (ii) adding at least one component K to the reaction mixture containing the polyether carbonate polyol, wherein a buffer system suitable for buffering a pH value in the region of pH 3.0 to 9.0 is used as component K, wherein the component K is free from compounds containing P—OH— groups.

A processfor producing a (poly)ol block copolymer comprising the reaction of a DMC catalyst with a polycarbonate or polyester (poly)ol (co)polymer and ethylene oxide, and optionally one or more other alkylene oxides, to produce a (poly)ol block copolymer wherein > 70% of the copolymer chain ends are terminated by primary hydroxyl groups, and the copolymers and products incorporating such copolymers.

Processes and production plants for preparing a polyol. The process includes continuously producing an intermediate polyol in a first reactor, b) continuously discharging the intermediate polyol from the first reactor, continuously mixing the intermediate polyol with an aqueous solutions of alkali metal to provide a mixture comprising the intermediate polyol, alkali metal, and water, continuously dehydrating the mixture comprising intermediate polyol, alkali metal, and water, thereby continuously producing a dehydrated mixture comprising the intermediate polyol and the alkali metal, transferring the dehydrated mixture to a second reactor, and producing the polyether polyol in the second reactor by feeding an alkylene oxide to the second reactor to thereby react the intermediate polyol with the alkylene oxide in the presence of the alkali metal.

The method for producing a polyalkylene glycol of the present invention is a method for producing a polyalkylene glycol, including performing a polymerization reaction of an alkylene oxide with a composite metal catalyst, the polymerization reaction being performed in the presence of an organic solvent in an amount of 10 to 90 mass % based on the polyalkylene glycol to be produced.

The invention relates to a process for preparing a polyoxyalkylene carbonate polyol by reacting a polyoxyalkylene polyol with a cyclic carbonate in the presence of an amine catalyst. The invention further relates to polyoxyalkylene carbonate polyols obtainable using the method according to the invention and to a process for preparing polyurethanes by reacting the polyoxyalkylene carbonate polyols according to the invention with polyisocyanates.

The present invention relates to a process for preparing a polyester-polyether polyol block copolymer by reaction of an H-functional starter substance with lactone in the presence of a catalyst to afford a polyester followed by reaction of the polyester from step i) with alkylene oxides in the presence of a catalyst (B), wherein the lactone is a 4-membered lactone. The invention further relates to the polyester-polyether polyol block copolymer obtainable by the present process.

A process for transitioning a reactor from base-catalyzed polyol production to double metal cyanide (DMC)-catalyzed polyol production is described. The process includes discharging a base-catalyzed and un-neutralized product mixture from a reactor, and adding an acidified polyether polyol starter and DMC catalyst mixture to the reactor. A DMC-catalyzed polyol production reaction can then be conducted in the reactor without intermediate washing or rinsing of the reactor, and without catalyst deactivation from base or alkaline hold-up.

The invention relates to polyoxyalkylenes having pendant long-chain acyloxy radicals and to a process for preparation thereof by an alkoxylation reaction using double metal cyanide (DMC) catalysts.

The present invention relates to a process for producing hydrosilylatable, eugenol-based polyethers, to the conversion thereof into polyether siloxanes and also to the products that may be produced by this process and to the use of said products as surfactants.

Polyethers are prepared by polymerizing an alkylene oxide in the presence of a double metal cyanide catalyst complex and certain M.sup.5 metal or semi-metal compounds. The double metal cyanide catalyst complex contains 0 5 to 2 weight percent potassium. The ability of this catalyst system to tolerate such high amounts of potassium permits the catalyst preparation procedure to be simplified and less expensive.