Efficient Organocatalyzed ATRP in both Organic and Aqueous Media via AIE photocatalysts

Organocatalyzed atom transfer radical polymerization (O-ATRP) presents a metal-free alternative to traditional ATRP. As a light-mediated method, it utilizes organic photoredox catalysts (PCs) to produce polymers with well-defined architectures. The development of highly efficient PCs operable in diverse solvents is crucial for advancing O-ATRP. In this work, we firstly demonstrated the application of aggregation-induced emission (AIE) photoredox catalysts in O-ATRP. Due to the aggregation-enhanced intersystem crossing and prolonged excited-state lifetime in aqueous aggregates, AIE-PC exhibited superior catalysis performance for O-ATRP in both organic and aqueous media. With the catalysis of AIE-PC, 95 % methyl methacrylate conversion in DMF (Ð = 1.11, Mn = 32.1 kDa) and 90 % DMAEMA conversion in aqueous media (Ð = 1.22, Mn = 31.6 kDa) at 100 ppm catalyst loading were achieved. Furthermore, well-defined block copolymers (PDMAEMA-b-POEGMA500) were successfully synthesized in aqueous media. Even under sunlight (30 mW cm-2) irradiation for 4 h, the polymerization of MMA was successfully initiated, achieving 66 % conversion. This work demonstrates the promising application of AIE-PC in O-ATRP whether in organic phase or aqueous media.