abstract |
A polymer dispersant for pigments based on an acrylic graft copolymer wherein the graft copolymer has a weight average molecular weight of at least 3000 and has 10 to 90 % by weight of a polymeric backbone and 90 to 10 % by weight of macromonomer side chains attached to the backbone and wherein the graft copolymer has at least about 1 % by weight of a pigment anchoring group selected from the group consisting of an aromatic ester group, aromatic amine group, and quaternary ammonium group, or mixtures thereof, attached to the backbone or the macromonomer. These materials disperse a wide variety of pigments and are useful in solvent borne coatings where they can provide improved efficiency of pigment use, lower paint viscosity, and reduced emission of volatile organic solvent. |