Photo-induced atom transfer radical polymerization of MMA with chlorophll A as photoinitiator

In this work, photoinduced free radical polymerization of methyl methacrylate (MMA) was performed at ambient temperature in dimethyl sulfoxide with chlorophll A as a photosensitizer. Well controlled polymerization of MMA was achieved. The linear first order plot of ln([M](0)/[M]) vs time was observed. Well-defined polymethyl methacrylates (PMMA) with narrow molecular weight distribution (M-w/M-n) were prepared. It indicated that the polymerization was controllable. The chain-end fidelity was demonstrated by H-1 NMR spectra. Chain extension experiments demonstrated the living feature of polymerization. The initiation and moderation of polymerization were manipulated by the periodic light on-off experiments.