An atom transfer radical polymerization system: catalyzed by an iron catalyst in PEG-400†
A green and highly efficient AGET ATRP (activators generated by electron transfer for atom transfer radical polymerization) system was constructed in the absence of any additional ligands, using FeCl3·6H2O as a catalyst, and methyl methacrylate as a model monomer in polyethylene glycol 400 (PEG-400). The effects of various factors, such as the type of ATRP initiator, the molecular weight of PEG and the reducing agent type, polymerization temperature as well as solvent, on the polymerization were investigated. Polymerization kinetics demonstrated that the polymerization was a controlled/“living” process with molecular weight increasing linearly with conversion while maintaining a low molecular weight distribution. The living feature was further confirmed by chain extension experiments.