Process for the Preparation of Random Radical Copolymers, and Active Substance Compositions Obtainable Therefrom

A process for preparing a random radical copolymer comprising dissolving

• a) at least one olefinically unsaturated sulfonic acid of the formula (I),
• where
• n is 0 to 10;
• X is O or NR5;
• R1 is hydrogen or methyl;
• R2, R3 independently of one another are hydrogen or C1- to C6-alkyl and
• R5 is hydrogen, alkyl, aryl, alkylaryl, arylalkyl, alkoxyalkyl, aryloxyalkyl, alkoxyaryl, hydroxyalkyl, (di)alkylaminoalkyl, (di)alkylaminoaryl, (di)arylaminoalkyl, alkylarylaminoalkyl or alkylarylaminoaryl, it being possible for the aryl radicals to be monosubstituted or polysubstituted,
• salts thereof or mixtures of acid and salts and
• b) at least two structurally different olefinically unsaturated monomers of the formula (II),
• where
• Y is O or NR7;
• R5 is hydrogen or methyl;
• R6 is alkyl, hydroxyalkyl, (di)alkylaminoalkyl or (di)alkylaminoaryl and
• R7 is hydrogen, alkyl, aryl, alkylaryl, arylalkyl, alkoxyalkyl, aryloxyalkyl, alkoxyaryl, hydroxyalkyl, (di)alkylaminoalkyl, (di)alkylaminoaryl, (di)arylaminoalkyl, alkylarylaminoalkyl or alkylarylaminoaryl, it being possible for the aryl radicals to be monosubstituted or polysubstituted,
• and
• c) if appropriate, one or more olefinically unsaturated monomers which differ structurally from components (a) and (b), and
• d) at least one initiator
• either in (i) a solvent mixture comprising water and a water-soluble organic solvent with a boiling point of less than 140° C. or (ii) in one or more pure alcohols by heating, and polymerizing the monomer to afford the random copolymer.

A random radical copolymer, obtainable by polymerizing

• a) at least one olefinically unsaturated sulfonic acid of the formula (I),
• wherein
• X is NH or oxygen;
• R1 is methyl or hydrogen;
• R2 and R3 are methyl or hydrogen and
• n is 1,
• salts thereof or mixtures of acid and salts, and
• b1) at least one olefinically unsaturated monomer of the formula (IIa),
• where
• Y is oxygen or NR7;
• R5 is hydrogen or methyl;
• R6′ is C1-C6-alkyl and
• R7 is hydrogen, alkyl, aryl, alkylaryl, arylalkyl, alkoxyalkyl, aryloxyalkyl, alkoxyaryl, hydroxyalkyl, (di)alkylaminoalkyl, (di)alkylaminoaryl, (di)arylaminoalkyl, alkylarylaminoalkyl or alkylarylaminoaryl, it being possible for the aryl radicals to be monosubstituted or polysubstituted,
• b2) at least one olefinically unsaturated monomer of the formula (IIb),
• wherein
• R5 is methyl or hydrogen and
• R6″ is C7-C20-alkyl
• and
• c) if appropriate, at least one further olefinically unsaturated monomer which differs structurally from component (b).