Process for preparing stabilized polymer dispersion

Claim 1

A process for preparing a stabilized polymer dispersion in an organic liquid in which the principal polymer comprises (a) a plurality of stabilizer components which are polymers of one or more ethylenically unsaturated acrylic monomers, and (b) a core component composed of acrylic polymers; substantially all of the stabilizer components being grafted to the core component at one of the stabilizer ends, the process comprising the following steps: (a) preparing the stabilizer component by polymerizing one of more ethylenically unsaturated acrylic monomers at least one of said monomers containing a reactive functional group, using a catalytic chain transfer agent containing Co +2 to form a stabilizer component having an ethylenically unsaturated terminal group and at least one reactive functional group, wherein the reactive functional group is selected from the group consisting of carboxyl, hydroxy, anhydride, isocyanate amine or silane, and then (b) preparing the core component by polymerizing one or more acrylic monomers while they are in contact with stabilizer components, steps (a) and (b) being conducted in an organic liquid which is a solvent for the stabilizer components but a non-solvent for the core component.