Polymerization-Induced Self-Assembly via RAFT-Mediated Emulsion Polymerization of Methacrylic Monomers

Polymerization-induced self-assembly via reversible addition-fragmentation transfer (RAFT)-mediated emulsion polymerization has served as a versatile platform for scalable preparation of well-defined block copolymer nanoparticles. However, kinetically trapped spherical micelles rather than higher-order morphologies are typically prepared by RAFT-mediated emulsion polymerization. Moreover, the mechanism for morphological evolution under RAFT-mediated emulsion polymerization conditions is still unclear. Herein, we report a redox-initiated RAFT-mediated emulsion polymerization of methacrylic monomers at relatively low temperatures. A diverse set of morphologies have been prepared by using glycidyl methacrylate (GlyMA) as the core-forming monomer. Effects of reaction temperature, molecular weight of macro-RAFT agent, degree of polymerization of PGlyMA, and monomer concentration on RAFT-mediated emulsion polymerization have been studied in detail. To give more insights into the mechanism of morphological evolution, other methacrylic monomers were also employed for RAFT-mediated emulsion polymerization. Finally, taking advantage of the intrinsic mechanism of RAFT-mediated emulsion polymerization, cross-linking has been explored for the preparation of higher-order morphologies. The current study not only expands the scope of RAFT-mediated emulsion polymerization for preparing various block copolymer nano-objects but also provides important insights into the morphological evolution under RAFT-mediated emulsion polymerization conditions.