Oxygen tolerance in controlled radical polymerizations has been an active field of study in recent years. Herein, we report a photocontrolled, additive-free iniferter polymerization that operates in completely open vials utilizing the "polymerizing through oxygen" mechanism. Trithiocarbonates are directly activated with high intensity 450 nm light to produce narrowly dispersed (Mw/Mn = 1.1-1.6) polyacrylates and polyacrylamides. Living behavior is demonstrated through chain extension, block copolymer synthesis, and control over molecular weight through varying the monomer:iniferter ratio. A slight increase in induction period is observed for the open vial polymerization compared to the air-free reaction, but polymers with similar Mn and Mw/Mn values are produced after 30-60 minutes of irradiation. This system will provide a convenient platform for living additive manufacturing because of its fast reaction time, air tolerance, wide monomer scope, and lack of any additives beyond the monomer, iniferter, and DMSO solvent.
Bibliographical noteFunding Information:
The authors thank C. Perkinson and Prof. M. Bawendi for their help with the absolute irradiance measurements. We acknowledge the National Science Foundation (NSF CHE-1629358) for support of this work. This work was supported in part by the MRSEC Program of the NSF under award DMR 14-19807. J. R. L. gratefully acknowledges the National Institutes of Health for a postdoctoral fellowship (1F32GM126913-01A1).
© 2019 The Royal Society of Chemistry.