Abstract: The invention relates to starting compounds which can be used for the preparation of polyurethanes and can be prepared by reaction of hydroxyl-containing oligomers of formaldehyde.

Abstract: The invention relates to a process for preparing DMC catalysts by reaction of cyanometalate compounds with metal salts, wherein the reaction is carried out in ionic liquids as solvents or suspension media.

Abstract: The invention relates to a process for the continuous preparation of polyether alcohols by reacting H-functional initiators with alkylene oxides using basic catalysts, wherein at least one initiator is metered with at least one alkylene oxide continuously into a back-mixing reactor and the reaction product is removed continuously from the back-mixing reactor.

Abstract: A process for preparing polyether polyols by reaction of the following starting materials: a) one or more alkylene oxides and, if appropriate, carbon dioxide and also b) one or more H-functional starter substances, in the presence of a catalyst, in a reaction unit having a plurality of parallel layers A, B which are microstructured so that each layer has a multiplicity of channels which are arranged parallel to one another and form a continuous flow path from one side of the plate to the opposite side of this, wherein a distribution device for introduction of the starting materials and the catalyst is provided at one end of the channels of the layers A and a collection device for the reaction mixture is provided at the other end of these is proposed.

Abstract: The invention provides a process for preparing polyether alcohols by adding alkylene oxides onto H-functional starter substances using DMC catalysts, which comprises, in a first step, adding propylene oxide or a mixture of propylene oxide and ethylene oxide onto H-functional starter substances and, in a second step, transferring the product thus formed into a tubular reactor in which mixtures of ethylene oxide and propylene oxide are metered in at least two metering points, the proportions of ethylene oxide and propylene oxide in the mixtures metered in in the first and in the second step being different, the proportions of ethylene oxide and propylene oxide in the mixtures metered in at least two metering points in the second step being different, and the mixture metered in in the second step, at least at the last metering point, comprising at least 40% by weight of ethylene oxide.

Abstract: The invention relates to polyether alcohols, to a process for preparing polyether alcohols by reacting alkylene oxides in the presence of a double metal cyanide (DMC) catalyst with at least one saturated OH component which may, if appropriate, have previously been reacted with an alkylene oxide, wherein an antioxidant is added before or during the reaction, and also to the further processing of the polyether alcohols to form polyurethanes.

Abstract: The invention provides a process for continuously preparing polyether alcohols using DMC catalysts, which comprises, in a first step, in a continuous reactor, adding alkylene oxides onto H-functional starter substances and transferring the output of this reactor to a second step in a reactor which is divided by closed trays into mutually separate sections, known as compartments, which are connected to one another by external pipelines, in which the output of the reactor from the first step of the reaction passes through the compartments in succession.

Abstract: The invention provides a process for preparing polyether alcohols by adding alkylene oxides onto H-functional starter substances using DMC catalysts, which comprises, in a first step, adding propylene oxide or a mixture of propylene oxide and ethylene oxide onto H-functional starter substances and, in a second step, transferring the product thus formed into a tubular reactor in which mixtures of ethylene oxide and propylene oxide are metered in at least two metering points, the proportions of ethylene oxide and propylene oxide in the mixtures metered in in the first and in the second step being different, the proportions of ethylene oxide and propylene oxide in the mixtures metered in at least two metering points in the second step being different, and the mixture metered in in the second step, at least at the last metering point, comprising at least 40% by weight of ethylene oxide.

Abstract: The invention provides a process for continuously preparing polyether alcohols by adding alkylene oxides to H-functional starter substances using a DMC catalyst, comprising the steps of a) preparing a precursor by continuously metering an H-functional starter substance, an alkylene oxide or a mixture of at least two alkylene oxides and the required amount of DMC catalyst into a continuous reactor, b) continuously withdrawing the precursor from step a) from the reactor, c) continuously metering the product from step a), an alkylene oxide different from that in step a) or a mixture of at least two alkylene oxides different from that in step a) and, if appropriate, the required amount of DMC catalyst into a further continuous reactor.

Abstract: The invention relates to polyether alcohols, to a process for preparing polyether alcohols by reacting alkylene oxides in the presence of a double metal cyanide (DMC) catalyst with at least one saturated OH component which may, if appropriate, have previously been reacted with an alkylene oxide, wherein an antioxidant is added before or during the reaction, and also to the further processing of the polyether alcohols to form polyurethanes.

Abstract: The invention relates to a process for the continuous preparation of polyether alcohols by reaction of alkylene oxides with H-functional starter substances in the presence of DMC catalysts, which comprises, at the beginning of the process a) firstly placing initial charge material and DMC catalyst in a reactor, b) metering in alkylene oxide so that the metering rate which is maintained for continuous operation of the reactor is reached in a time of from 100 to 3000 seconds, c) metering in starter substance during or after step b) so that the metering rate which is maintained for continuous operation of the reactor is reached in a time of from 5 to 500 seconds, d) after the fill level in the reactor which is desired for continuous operation of the reactor has been reached, taking product off continuously from the reactor while at the same time metering in starter substance and alkylene oxides in such an amount that the fill level in the reactor remains constant and metering in DMC catalyst so that the catalyst

Abstract: Process for preparing polyether polyols having an end block of ethylene oxide by addition of alkylene oxides onto H-functional starter substances, in which A) a polyether polyol precursor is prepared by means of double metal cyanide (DMC) catalysis in a semicontinuous mode of operation in which previously prepared polyether polyol together with the DMC catalyst are placed in a reactor and H-functional starter substance and propylene oxide are added continuously, B) the polyether polyol precursor from stage A) is reacted with propylene oxide or an ethylene oxide/propylene oxide mixture in the presence of the DMC catalyst in a continuously operating reactor to give a polyether polyol intermediate, C) the intermediate from stage B) is mixed with an alkali metal hydroxide as catalyst and D) reacted with ethylene oxide in a continuously operating reactor to give the final product, E) the catalyst is separated off from the final product obtained in stage D).

Abstract: A process for preparing polyether polyols comprises A) preparing a polyether polyol precursor, B) preparing a suspension of a DMC catalyst in a polyol, C) activating the DMC catalyst by bringing it into contact with an alkylene oxide, giving an activated DMC catalyst suspension, D) adding the activated DMC catalyst suspension from step C) to the polyether polyol precursor, E) reacting the polyether polyol precursor with alkylene oxide and, if appropriate, an H-functional starter substance in the presence of the activated DMC catalyst.

Abstract: The invention relates to starting compounds which can be used for the preparation of polyurethanes and can be prepared by reaction of hydroxyl-containing oligomers of formaldehyde.

Abstract: The present invention relates to polyetherols are prepared by a process comprising the reaction of at least one alkylene oxide with at least one initiator compound in the presence of at least one double metal cyanide compound to give a polyetherol and the treatment of the resulting polyetherol with steam or with an inert gas and steam, and the polyetherols obtainable by such a process as well as the use thereof for the synthesis of polyurethanes.

Abstract: Polyetherpolyols are prepared by reacting diols or polyols with ethylene oxide, propylene oxide, butylene oxide or a mixture thereof in the presence of a multimetal cyanide complex catalyst by a process which is carried out in a vertical, highly cylindrical reactor having a central stirrer and having heat exchanger plates through which a heat-exchange medium flows and which are arranged essentially in the longitudinal direction of the reactor, at an angle ? of from 0 to 70° in the direction of rotation of the stirrer relative to the reactor radius.

Abstract: Process for preparing polyether polyols having an end block of ethylene oxide by addition of alkylene oxides onto H-functional starter substances, in which A) a polyether polyol precursor is prepared by means of double metal cyanide (DMC) catalysis in a semicontinuous mode of operation in which previously prepared polyether polyol together with the DMC catalyst are placed in a reactor and H-functional starter substance and propylene oxide are added continuously, B) the polyether polyol precursor from stage A) is reacted with propylene oxide or an ethylene oxide/propylene oxide mixture in the presence of the DMC catalyst in a continuously operating reactor to give a polyether polyol intermediate, C) the intermediate from stage B) is mixed with an alkali metal hydroxide as catalyst and D) reacted with ethylene oxide in a continuously operating reactor to give the final product, E) the catalyst is separated off from the final product obtained in stage D).

Abstract: In a process for producing polyurethanes by reacting at least one polyisocyanate with at least one compound containing at least two hydrogen atoms which are reactive toward isocyanate groups, the compound having at least two active hydrogen atoms which is used is at least one polyether alcohol prepared by addition of alkylene oxides onto H-functional initiator substances by means of multimetal cyanide catalysis and the reaction is carried out in the presence of at least one metal salt.

Abstract: The invention relates to a process for the continuous preparation of polyether alcohols by reaction of alkylene oxides with H-functional starter substances in the presence of DMC catalysts, which comprises, at the beginning of the process a) firstly placing initial charge material and DMC catalyst in a reactor, b) metering in alkylene oxide so that the metering rate which is maintained for continuous operation of the reactor is reached in a time of from 100 to 3 000 seconds, c) metering in starter substance during or after step b) so that the metering rate which is maintained for continuous operation of the reactor is reached in a time of from 5 to 500 seconds, d) after the fill level in the reactor which is desired for continuous operation of the reactor has been reached, taking product off continuously from the reactor while at the same time metering in starter substance and alkylene oxides in such an amount that the fill level in the reactor remains constant and metering in DMC catalyst so that the catalys

Abstract: Catalyst suspensions for the ring-opening polymerization of alkylene oxides comprise a) at least one multimetal cyanide compound having a crystalline structure and a content of platelet-shaped particles of at least 30% by weight, based on the multimetal cyanide compound, and b) at least one organic complexing agent c) water and/or d) at least one polyether and/or e) at least one surface-active substance, with the proviso that at least component a) and at least two of the components b) to e) have to be present.