Viscosity reducers for polyether polyols

The present invention relates to a method for preparing a polyurethane, comprising the steps of: i) providing at least one polyisocyanate-containing polyisocyanate component; ii) providing a at least one polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol-containing polyol component, wherein the polyol component includes a polyol ester of a polyol and a monocarboxylic acid; iii) contacting the polyisocyanate component with the polyol component to form a polyurethane. The invention also relates to the product obtainable by this process polyurethane, a a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol-containing polyol component, a method for producing a a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol -containing polyol component obtainable by this process, a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol-containing polyol component, the use of such a polyether polyol, a polyester polyol or a mixture of a polyether polyol and a polyester polyol-containing polyol component as well as the use of a polyol ester.