What happens in the dark? Assessing the temporal control of photo-mediated controlled radical polymerizations

Neil D Dolinski; Zachariah A Page; Emre H Discekici; David Meis; In-Hwan Lee; Glen R Jones; Richard Whitfield; Xiangcheng Pan; Blaine G McCarthy; Sivaprakash Shanmugam; Veronika Kottisch; Brett P Fors; Cyrille Boyer; Garret M Miyake; Krzysztof Matyjaszewski; David M Haddleton; Javier Read de Alaniz; Athina Anastasaki; Craig J Hawker

doi:10.1002/pola.29247

What happens in the dark? Assessing the temporal control of photo-mediated controlled radical polymerizations

J Polym Sci A Polym Chem. 2019 Feb 1;57(3):268-273. doi: 10.1002/pola.29247. Epub 2018 Nov 8.

Authors

Neil D Dolinski¹, Zachariah A Page¹, Emre H Discekici^{1

2}, David Meis¹, In-Hwan Lee¹, Glen R Jones³, Richard Whitfield³, Xiangcheng Pan⁴, Blaine G McCarthy⁵, Sivaprakash Shanmugam⁶, Veronika Kottisch⁷, Brett P Fors⁷, Cyrille Boyer⁶, Garret M Miyake⁵, Krzysztof Matyjaszewski⁴, David M Haddleton³, Javier Read de Alaniz^{1

2}, Athina Anastasaki^{1

3}, Craig J Hawker^{1

2}

Affiliations

¹ Materials Department and Materials Research Laboratory, University of California Santa Barbara, Santa Barbara CA 93106.
² Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara CA 93106.
³ Department of Chemistry, University of Warwick, Coventry, CV47 AK (UK).
⁴ Center for Macromolecular Engineering, Carnegie Mellon University, Pittsburgh, PA 15213.
⁵ Department of Chemistry, Colorado State University, Fort Collins, CO 80523.
⁶ Center for Advanced Macromolecular Design, School of Chemical Engineering, The University of New South Wales, Sydney NSW 2052, (Australia).
⁷ Department of Chemistry, Cornell University, Ithaca, NY 14850.

Abstract

A signature of photo-mediated controlled polymerizations is the ability to modulate the rate of polymerization by turning the light source 'on' and 'off.' However, in many reported systems, growth can be reproducibly observed during dark periods. In this study, emerging photo-mediated controlled radical polymerizations are evaluated with in situ ¹H NMR monitoring to assess their behavior in the dark. Interestingly, it is observed that Cu-mediated systems undergo long-lived, linear growth during dark periods in organic media.

Keywords: controlled radical polymerization; in-situ monitoring; photopolymerization.

Grants and funding

R35 GM119702/GM/NIGMS NIH HHS/United States