abstract |
The invention relates to a process for the preparation of a water-in-oil polymer dispersion comprising the steps of (a) preparing a water-in-oil monomer dispersion comprising water, an oily substance, a water-in-oil emulsifier, a polymeric coagulant, a radically polymerizable (alk)acrylic acid derivative, and optionally one or more radically polymerizable, ethylenically unsaturated co-monomers; and (b) radically polymerizing the radically polymerizable (alk)acrylic acid derivative and the optionally present one or more radically polymerizable, ethylenically unsaturated co-monomers thereby yielding an intercalated polymer; wherein the polymeric coagulant is derived from at least one cationic monomer selected from the group consisting of (alk)acrylamidoalkyltrialkyl ammonium halides, (alk)acryloyloxyalkyl trialkyl ammonium halides, and alkenyl trialkyl ammonium halides. |