Blue‐light‐induced atom transfer radical polymerization enabled by iron/copper dual catalysis

Abstract

Abstract Photoinduced initiators for continuous activator regeneration atom transfer radical polymerization (PICAR ATRP) using sodium pyruvate and blue light ( λ max = 456 nm) is reported. Water‐soluble oligo(ethylene oxide) methyl ether methacrylate (OEOMA 500 ) was polymerized under biologically relevant conditions. Polymerizations were conducted with 1000 ppm (with respect to the monomer) concentrations of CuBr 2 , tris(2‐pyridylmethyl)amine, and 1000 ppm or less FeCl 3 as a cocatalyst in water. Well‐defined polymers with up to 90% monomer conversion, high molecular weights ( M n > 190,000), and low dispersity (1.14 < Ð < 1.19) were synthesized in less than 60 min. The polymerization rate and dispersity were tuned by varying the concentration of sodium pyruvate (SP), iron, and supporting halide, as well as light intensity. The Cu/Fe dual catalysis provided oxygen tolerance enabling rapid, well‐controlled, aqueous PICAR ATRP of OEOMA 500 without deoxygenation.