Patent ID: 6884826

Claim:
A process for preparing a polyoxyalkylene polyol comprising the steps of: combining a starter compound having active hydrogen atoms with a double metal cyanide (DMC) catalyst; activating the double metal cyanide (DMC) catalyst with a first alkylene oxide monomer (AO 1 ); polyoxyalkylating the starter compound with a mixture of the first alkylene oxide monomer (AO 1 ) and a second alkylene oxide monomer (AO 1 /AO 2 ) in which the first alkylene oxide monomer (AO 1 ) content of the mixture decreases as content of the second alkylene oxide monomer (AO 2 ) increases over the course of the polyoxyalkylation such that AO 1 +AO 2 =100; digesting unreacted monomers of the first alkylene oxide (AO 1 ) and the second alkylene oxide (AO 2 ); and capping the polyol by adding the second alkylene oxide (AO 2 ) thereto, wherein the first alkylene oxide monomer (AO 1 ) and the second alkylene oxide monomer (AO 2 ) are different.