Mixtures comprising (A) at least one hydraulic or latently hydraulic binder, (B) at least one copolymer obtainable by reacting (α1) at least one ethylenically unsaturated comonomer having at least one functional group selected from COOH groups, sulfonic acid groups, nitrile groups, hydroxyalkyl groups and amino groups, or (α2) at least one (co)polymer of at least one ethylenically unsaturated comonomer having at least one functional group selected from COOH groups, sulfonic acid groups, nitrile groups, hydroxyalkyl groups and amino groups, with (β) at least one oligomeric or polymeric compound obtainable by reacting (a) at least one ethylenically unsaturated di- or polycarboxylic acid or anhydride or ester thereof with (b) at least one at least trifunctional alcohol and (c) at least one compound of the general formula I in which the variables are each defined as follows: R1 is selected from C1-C4-alkyl and hydrogen, A is the same or different and is selected from C2-C6-alkylene, n is in the range from 4 to 40, and (d) optionally at least one further compound having at least one COOH group or at least one alcoholic OH group per molecule.