METHOD OF PRODUCING WATER-SOLUBLE POLYMER DISPERSIONS CONTAINING A HIGH CONCENTRATION OF POLYMER

摘要

The invention concerns a method of producing low-viscosity water-soluble waterbased polymer dispersions containing high concentrations of a polymer (A) with an average molecular weight Mw of at least 5 x 105 Daltons made from watersoluble monomers, hydrophobic monomers and, optionally, amphiphilic monomers and further containing at least one polymeric dispersant (D). In a first step, an aqueous dispersion (PD) of the polymer (A) and the at least one polymeric dispersant (D) is prepared. In a second step, a highly concentrated aqueous dispersion (PD') is produced from the aqueous dispersion (PD) by removing water and, in a third step, an aqueous dispersion (PD") with a high polymer concentration is produced by adding an aqueous dispersion of at least one polymeric dispersant (D) to the concentrated dispersion (PD'). The second and third steps may be repeated successively.