PROCEDURE FOR OBTAINING WATERPROOF DISPERSIONS OF COPOLYMERS FROM HYDROPHYL AND HYDROPHOBIC MONOMERS, AS WELL AS COPOLYMERS OBTAINABLE FROM THE SAME AND ITS APPLICATIONS.

摘要

Process for obtaining an aqueous dispersion of copolymers by polymerization through radicals of monomers with ethylenic unsaturation in aqueous medium, containing: (a) 10 to 90% by weight of at least one hydrophilic monomer A, which has a N-vinyl group, and whose polymerization rate has a maximum at pH values above 7; (b) 10 to 90% by weight of at least one monomer with hydrophobic monoethylenic unsaturation B, whose polymerization rate has a maximum at pH values below 7; (c) 0.01 to 20% by weight, based on the total monomers present in the reaction medium, at least one initiator through water-soluble or water-insoluble radicals, or a mixture of initiators through water-soluble radicals with water-insoluble radical initiators, characterized in that, in the development of the polymerization reaction, the pH value is controlled such that the pH value drops by 2 to 5 units in the polymerization development, between the beginning and the end of the reaction.