Method for manufacturing polyether ester polyols

Preparing (P1) a first polyether ester polyol involves reacting starting compounds having Zerewitinoff-active hydrogen atoms with at least one alkylene oxide in presence of at least one amine selected from tertiary amines and optionally substituted imidazole, and at least one fatty acid ester, where the fatty acid ester is added before, during, or after the metered addition of alkylene oxide and, before the metered addition of the alkylene oxide, a second polyether ester polyol is mixed in an amount of 3-20 wt.%. An independent claim is included for a solid or foamed polyurethane material produced from at least one polyether ester polyol obtained by the process (P1) and optionally further isocyanate-reactive components, at least one organic polyisocyanate, optionally in presence of at least one foaming agent, optionally in presence of at least one catalyst, and optionally in presence of further additives.