Visible-Light-Induced Controlled Polymerization of Hydrophilic Monomers with Ir(ppy)3 as a Photoredox Catalyst in Anisole

With fac -Ir(ppy) 3 as photoredox catalyst and ethyl 2-bromoisobutyrate (EBiB) as initiator, the homopolymerization of methyl methacrylate (MMA) in different solvents, such as N , N -dimethylformamide (DMF), acetonitrile, and anisole are run under irradiation of an LED lamp. The results show that anisole is a better solvent for the polymerization with regard to the polydispersity index (PDI). A well-controlled polymerization of poly(ethylene glycol) methyl ether methacrylate (PEGMA) is demonstrated and the clean block copolymer of PMMA- b -PPEGMA is prepared with PDI less than 1.3; however, the 2-(dimethylamino) ethyl methacrylate (DMAEMA) polymerization is poorly controlled. With the PMMA as macromolecular initiator, the block copolymer PMMA- b -PDMAEMA can be prepared with PDI around 2.0.