The continuous trend of transition from solventbased coatings to waterborne systems is a major driving force in the development of new formulation additives. With increased volatile organic compound (VOC) restrictions and sustainability targets, dispersing agents not only play an important role in helping the paint formulator achieve efficient processing and formulation flexibility, but also ensure the maximum coating performance, e.g., coloristics. Controlled free radical polymerization (CFRP) gives access to novel block copolymers with well-defined structures, where it is well known that selection of monomer chemistry and the chain length of AB-block copolymers are key design parameters. In addition, structural perfection plays an important role in optimization. These factors combined enable the design of new dispersants with effective pigment anchoring groups in combination with good compatibility towards different resin systems.In this paper, we show how our recent developments using nitroxyl-mediated polymerization resulted in high-performance dispersing agents, with focus on the use of pigments in waterborne and high-solids applications. In addition, we show how detailed analysis, e.g., gradient chromatography, assisted us in the determination of the level of structural perfection that is necessary to achieve optimal results and what impact deviations from the ideal structure have on performance. These dispersants perfectly meet the requirements for modern VOC-reduced high-quality paints, offering superior rheology and stability of pigment concentrates with favorable coloristic properties.
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