One-pot synthesis of block copolymer dispersant by ICAR ATRP with ppm copper catalyst and the dispersibility on pigment

Abstract

The controlled / living polymerization mechanisms have advantages on synthesizing the dispersant with defined structures and compositions, while encountering with individual drawbacks in industrial application. Based on the initiators for continuous activator regeneration atom transfer radical polymerization (ICAR ATRP) of oligo(ethylene oxide)methyl ether methacrylate (OEEMA) and glycidyl methacrylate (GMA) monomers, the diblock copolymers POEOMA-b-P(OEOEMA-co-GMA) were prepared. The GMA units were further modified with 3-mercaptopropionic acid (MPA) agent. The polymerization and modification procedure can be readily realized in a one-pot technology with complete monomer conversion (~100%) and high ring-opening efficiency (~100%), as well as low concentration copper catalyst (100 ppm). Using the MPA modified P(OEOEMA-co-GMA) as anchoring block, POEOMA as stabilizing block, the obtained block copolymers can be used as dispersant to disperse and stabilize the pigment yellow 14. The standing experiment, optical microscope (OM) and dynamic light scattering (DLS) measurements reached to a consistent conclusion that the absolute number of carboxyl groups on each chain modulate the dispersibility of the dispersions, rather than the relative content of carboxyl groups. This work provided a feasible one-pot technology to efficient dispersants.