Organocatalytic PET-RAFT polymerization with a low ppm of organic photocatalyst under visible light

The development of light-mediated controlled radical polymerization has benefited from the discovery of novel photocatalysts, which could allow precise light control over the polymerization process and the production of well-defined polymers. Here, we introduce oxygen-doped anthanthrene (ODA) as an effective organic photocatalyst for photoinduced energy/electron transfer reversible addition-fragmentation chain-transfer (PET-RAFT) polymerization. ODA photocatalysts feature strong visible light absorption (epsilon(455 nm) up to 2.4 x 10(4) M(-1)cm(-1)), ease-of-synthesis, a certain oxygen tolerance, and high stability, which enable the photo-regulated RAFT polymerization with an extremely low catalyst loading (0.1-10 ppm) and excellent control under visible light or sunlight. Furthermore, this organocatalytic living radical process is adaptable to the polymerization of a range of monomers including methyl methacrylate, butyl acrylate, styrene, and N,N-dimethyl acrylamide, and also the synthesis of diblock and decablock copolymers under metal-free conditions.

Automated summary

The development of light-mediated controlled radical polymerization has been advanced by the discovery of oxygen-doped anthanthrene (ODA) as an effective organic photocatalyst for photoinduced PET-RAFT polymerization. ODA photocatalysts feature strong visible light absorption, ease-of-synthesis, oxygen tolerance, and high stability, allowing for excellent control under extremely low catalyst loading conditions in visible light or sunlight. The organocatalytic living radical process using ODA is adaptable to a range of monomers and copolymers, and can be done under metal-free conditions.