NOVEL THICKENING AGENTS HAVING CATIONIC UNITS AND METHOD FOR PREPARING SAME

摘要

Cross-linked amphoteric or cationic polymers, a method for preparing same and the uses thereof as a thickening agent and/or an emulsifier and/or a stabilising agent in aqueous compositions or emulsions, are disclosed. The polymer prepared by polymerising at least one cationic monomer and optionally other non-ionic and/or anionic monomers in the presence of a cross-linking agent and optionally a transfer agent must have an MBA (methylene bis acrylamide) cross-linking agent concentration higher than 150 ppm relative to the polymer, and preferably higher than 300 ppm, or concentrations of other cross-linking agents that lead to equivalent cross-linking levels; a cationic monomer to total monomer ratio of at least 25 % mol; and, in the case of polymerisation carried out under the same synthesis conditions BUT in the absence of a cross-linking agent, an intrinsic viscosity of less than 4.5 dl/g and preferably less than 4.0 dl/g, and more than 1.2, preferably more than 1.4 dl/g, and preferably more than 1.6 dl/g. The final composition is highly effective even at acidic pH values (pH < 7) and has an enhanced non-stringy texture.