The invention relates to a comb polymer having repeating units of at least one of the structures of formulae (I) to (IV) wherein R1 represents a polyoxyalkylene group and A represents an organic group, and wherein the comb polymer has end groups of the general formula (V) wherein R2 and R3 independent of each other are selected from a) organic groups having 1 to 24 carbon atoms and b) R1.