Abstract: The present invention relates to a method for producing a double metal cyanide (DMC) catalyst, comprising the reaction of an aqueous solution of a cyanide-free metal salt, an aqueous solution of a metal cyanide salt, an organic complex ligand, optionally a complex-forming component to form a dispersion, the dispersion being produced using a mixing nozzle and a peroxide. The invention further relates to double metal cyanide (DMC) catalysts obtainable by means of the method according to the invention and to the use of DMC catalysts to produce polyoxyalkylene polyols.

Abstract: 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.

Abstract: The present invention relates to a method for producing a double metal cyanide (DMC) catalyst, comprising the reaction of an aqueous solution of a cyanide-free metal salt, an aqueous solution of a metal cyanide salt, an organic complex ligand, optionally a complex-forming component to form a dispersion, the dispersion being produced using a mixing nozzle and a peroxide. The invention further relates to double metal cyanide (DMC) catalysts obtainable by means of the method according to the invention and to the use of DMC catalysts to produce polyoxyalkylene polyols.

Abstract: The invention provides a process for preparing polyesters by reacting an H-functional starter substance with a lactone in the presence of a Brønsted-acidic catalyst which comprises initially charging the H-functional starter substance and the Brønsted-acidic catalyst to form a mixture i) and subsequently adding the lactone to the mixture i), wherein the process is carried out without adding an aromatic solvent and wherein the H-functional starter substance is an OH-functional starter substance and/or a COOH-functional starter substance and wherein the lactone is a 4-membered ring lactone. The invention further provides polyesters obtainable by the method of the invention.

Abstract: The invention relates to a method for producing a polyoxyalkylene polyester polyol by reacting a polyoxyalkylene polyol with a lactone in the presence of a Brønsted acid catalyst, wherein the catalyst has a pKa value of 1 or less; the number-average molar mass of the polyoxyalkylene polyol is ?1000 g/mol, preferably ?1500 g/mol, particularly preferably ?2000 g/mol; and in the lactone a CH2 group is bonded to the ring oxygen. The invention further relates to polyoxyalkylene polyester polyols obtainable using the method according to the invention, and to a method for producing polyurethanes by reacting the polyoxyalkylene polyester polyols according to the invention with polyisocyanates.