| 摘要 |
A polymer dispersant for pigments based on an acrylic graft copolymer wherein the graft copolymer has a weight average molecular weight of 3,000-100,000 and comprises a polymeric backbone and macromonomer side chains attached to the backbone, wherein (1) the polymeric backbone is formed of polymerized ethylenically unsaturated monomers and (2) the side chains are macromonomers that are attached to the backbone at a single terminal point and are formed from polymerized ethylenically unsaturated monomers and have a weight average molecular weight of about 1,000-30,000 wherein the graft copolymer contains about 2 to 70% by weight, based on the weight of the graft copolymer, of polymerized ethylenically unsaturated monomers containing acetoacetate groups that are polymerized into the backbone, side chains, or both, and the acetoacetate groups are reacted with a primary amine to form a pendant acetoacetyl amine group on the graft copolymer which serves as the pigment anchoring group. These materials are effective in dispersing and stabilizing a wide range of pigments in solvent based systems and are particularly useful in forming pigment dispersions that are used in a variety of solvent borne coating compositions for automobiles and trucks, where they provide improved efficiency of pigment use, lower paint viscosity, and reduced emission of volatile organic solvent.
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