Method for producing polyether polyols

A process for the preparation of a first polyether polyol A and of a second, monofunctional polyether polyol B comprising:

• (i) preparing a solution or dispersion of one or more starter compounds (S-1), each having at least four Zerewitinoff-active hydrogen atoms, in one or more monofunctional starter compounds (S-2) at a weight ratio of S-1 to S-2 of from 20:80 to 85:15,
• (ii) reacting the solution or dispersion from step (i) with one or more alkylene oxides, optionally after addition of a catalyst, to form a reaction mixture that includes polyether polyol A that is a reaction product of the at least one starter compound (S-1) with one or more alkylene oxides and polyether polyol B that is a reaction product of the at least one monofunctional starter compound (S-2) with one or more alkylene oxides,
• (iii) optionally, removing any catalyst present from the reaction mixture formed in (ii), and
• (iv) separating the monofunctional polyether polyol B from the reaction mixture by distillation under reduced pressure or by stripping with inert gas or water to generate a residue containing polyether polyol A and up to 15 wt. % (in each case based on the sum of the wt. % of polyether polyol A and of the monofunctional polyether polyol B) monofunctional polyether polyol B.