Patent ID: 7803899
Filing Date: 2010-09-28
Classification: C08F,C08G

Abstract:
1. A method of preparing dry water-soluble polymer comprising: a) combining a water-soluble polymer in water with at least one dry polar solvent to form a mixture that separates into a first layer comprising a majority of said dry polar solvent and water and a second layer comprising a majority of said water-soluble polymer, wherein said water-soluble polymer is an ionene polymer, a polyaminoamide polymer, or a polyacrylamide/diallyldimethyl-ammonium halide copolymer; b) separating said first layer from said second layer; and c) drying said second layer to obtain a solid comprising said water-soluble polymer, wherein said water-soluble polymer having at least one polar solvent content or impurity level selected from: