Photoinduced Oxygen Reduction for Dark Polymerization

Photopolymerization systems for controlled/living radical polymerization (CLRP) have often been dependent on continuous irradiation to sustain radical production. Although this approach offers an opportunity to impose spatial and temporal control, it remains an energy inefficient process. As energy storage for CLRP remains an unexplored area in polymer chemistry, it may provide an opportunity for designing energy efficient polymerization. In this contribution, we propose a novel energy storage system where in situ production of hydrogen peroxide from molecular oxygen was achieved after a brief period of visible light irradiation in the presence of photo-organocatalyst and ascorbic acid. Upon ceasing irradiation, the slow generation of hydroxyl radicals from hydrogen peroxide in the presence of ascorbic acid allows for continuous radical generation in the dark. The highlight of this system stems from the fact that irradiation as brief as 5 min allows storage of enough energy as hydrogen peroxide to perform...