Patent ID: 8497318
Filing Date: 2013-07-30
Classification: C08F

Abstract:
1. A process for preparing a polymer by free-radical polymerization of a) at least one ethylenically unsaturated monocarboxylic acid and/or a salt thereof, b) at least one ethylenically unsaturated dicarboxylic acid and/or an anhydride and/or a salt thereof, in the presence of c) hypophosphorous acid and/or a salt thereof, comprising providing in a polymerization zone an initial charge that comprises at least a part of monomer component b) and adding a monomer feed, comprising at least a part of monomer component a) to the polymerization zone, wherein during the addition of the monomer feed at least a part of the hypophosphorous acid or a salt thereof is added to the polymerization zone.