Tailored design of well-defined comb-like copolymer dispersants for enhanced dispersion and stability of cerium oxide nanoparticle suspensions

Abstract

The development of effective dispersants for nanoparticle suspensions is crucial for enhancing the performance and stability of various functional materials. In this study, we investigated a series of comb-like block copolymers with well-defined structures, including both categories of block copolymers and uniformly composed random copolymers, as dispersants for cerium oxide (CeO₂) suspensions. Acrylic acid (AA) units were used for anchoring and electrostatic repulsion, while methoxy polyethylene glycol acrylate (MPEGA) units provided additional steric hindrance and solubility. We explored stabilization mechanisms involving polymer topologies, chain lengths, compositions, and molecular interactions from kinetic and thermodynamic perspectives. The results demonstrate significant improvements in dispersion stability with both categories of well-controlled copolymers, especially with uniformly composed random copolymers due to their uniformly distributed multi-point anchoring and balanced electrostatic and steric stabilization. This research not only enhances the fundamental understanding of polymer-nanoparticle interactions and polymer dispersants, but also provides valuable guidance for the tailored design of dispersants for specific industrial and scientific needs.