Abstract: Process for producing rigid polyurethane foams by reacting a) polyisocyanates with b) compounds having at least two hydrogen atoms which are reactive toward isocyanate groups in the presence of c) blowing agents, wherein the compounds having at least two hydrogen atoms which are reactive toward isocyanate groups comprise at least one polyether alcohol bi) which can be prepared by reacting aromatic amines with ethylene oxide and propylene oxide, with firstly propylene oxide and then ethylene oxide or a mixture of ethylene oxide and propylene oxide being added on in a first process step and the remaining amount of propylene oxide being added on in a second process step using a basic catalyst.

Abstract: A process for preparing double metal cyanide catalysts, comprising combining an aqueous solution of a metal salt of the formula M1m(X)n, with an aqueous solution of a cyanometallic acid of the formula HaM2(CN)b(A)c, where one or both aqueous solutions may comprises at least one water-miscible organic ligand selected from the group consisting of alcohols, aldehydes, ketones, ethers, polyethers, esters, ureas, amides, nitrites or sulfides, if desired, combining the aqueous suspension thus obtained with at least one water-miscible organic ligand selected from the above-mentioned group, which ligand may be identical to or different from any previously added ligand, and separating the resulting two-metal cyanide complex from the suspension.

Abstract: A process for treating polyether polyols prepared in a conventional manner by base-catalyzed reaction of H-functional initiator substances with alkylene oxides comprises a combination of a thermal-reactive step at a pH of less than 7 and a temperature above 60° C. and a thermal-distillative step in a countercurrent column using a purifying agent. The polyether polyols prepared according to the invention are used for producing low-fogging and low-odor PUR foams.

Abstract: In a process for producing flexible polyurethane foams by reactinga) organic and/or modified organic polyisocyanates withb) relatively high molecular weight compounds containing at least two reactive hydrogen atoms andc) if desired, low molecular weight chain extenders and/or cross linkersin the presence ofd) blowing agents,e) catalysts,f) flame retardants and, if desiredg) further auxiliaries and/or additives,the relatively high molecular weight compounds containing at least two reactive hydrogen atoms (b) comprise at least 10% by weight of polyether polyols which can be prepared by base-catalyzed reaction of lower alkylene oxides with OH-functional initiator substances and are subjected, during or after the molecular addition of alkylene oxide, to a combined thermal/distillative treatment at a water content of at most 0.1% by weight.The flexible PUR foam produced according to the present invention can be used in the automobile and furniture sectors and for producing flexible foam/textile composites.