Process for preparing polyether polyols

摘要

The present invention relates to a process for preparing polyether polyols by base-catalyzed addition of alkylene oxides (epoxides) onto starter compounds which are solid at room temperature and have Zerevitinov-active hydrogen atoms, a particular feature of which is that visually clear and/or homogeneous products are obtained even in the absence of solvents.

主权项

1. Process for preparing polyether polyols having n En blocks each comprising at least 75% by weight of oxyethylene units, and m Am blocks being different from the En blocks, where n and m are each natural numbers from 1 to 10 and at least one starter compound having at least one Zerevitinov-active hydrogen atom and a melting point of ≧40° C., comprising reacting the at least one starter compound with ethylene oxide and at least one further alkylene oxide compound in the presence of a catalyst, wherein the En block(s) are metered in under the conditions of the following inequation;Tn*x⁡(cat)*tnxn⁡(EO)>2.9⁢⁢in⁢[°C.⁢*⁢h](1) where
Tn is defined as the man reaction temperature in ° C. during the metered addition of the ethylene oxide for the En block, x(cat) is defined as the amount of catalyst used in mol, tn is defined as the metering time for the ethylene oxide in the En block in hours, xn (EO) is defined as the amount of ethylene oxide metered in for the En block in mol, and n is as defined above, and wherein the total content of oxyethylene units in the polyether polyols, based on the total mass of all the alkylene oxides metered in, is from 5 to 85% by weight.