Polymer architecture and the type of pigment affinic anchoring groups are key parameters to tailor dispersant performance.4,5 Good control of polymer architecture requires appropriate advanced polymerization techniques. Only very recently has the novel pioneering technique of "controlled free radical polymerization" (CFRP) been commercialized in the field of pigment dispersants.6 In this article we discuss acrylic block copolymer types of "controlled pigment dispersants" based on this technology and give examples of how the polymer design capabilities of CFRP offer improved solutions in pigment dispersion.
We developed new classes of sterically hindered alkoxyamine compounds, like special open chain NOR10, piperazinone-type NOR11, piperidine-type NOR12 and 7-ring heterocyclic NOR13, which allow the controlled polymerization of acrylates. These NOR polymerization regulators represent a versatile and robust toolbox for the synthesis of functional polyacrylates with controlled structure. Some representative examples of NOR compounds, which have been shown to be especially useful for the synthesis of polyacrylate dispersants, are shown in Figure 2.