The invention relates to a process for the preparation of copolymer in a continuous mode of operation in a polymerization apparatus, comprising a polymerization reactor having feed lines and an outflow, free radical polymerization initiator, an acid monomer and polyether macromonomer being passed as monomeric starting materials into the polymerization reactor through the feed lines, initiator, monomeric starting materials and copolymer-containing reaction composition thermostated at −20 to +120° C. being present in the polymerization reactor, copolymer-containing reaction composition being discharged from the polymerization reactor through the outflow, the introduction of the polyether macromonomer into the polymerization reactor being effected separately from the acid monomer in a manner such that the polyether macromonomer is mixed with the initiator, monomeric starting materials and copolymer-containing reaction composition in the polymerization reactor and comes into contact with the acid monomer for the first time thereby.