title: Time-Resolved EPR as a Tool to Investigate Oxygen Quenching in Photoinitiated Radical Polymerizations.
abstract: It is challenging to obtain absolute rate constants for the quenching of organic radicals by molecular oxygen because they often do not present absorbance in the UV-vis range. Here, it is shown that time-resolved EPR (chemically induced dynamic electron polarization, or CIDEP) spectroscopy is useful in establishing rate constants for the addition of benzoyl radicals to molecular oxygen. It was found that benzoyl radicals are particularly reactive toward O2 and can, therefore, act as oxygen scavengers in the initiating phase of radical polymerizations. Kinetic simulations underpin this reactivity.
authors.affiliation: Institute of Physical and Theoretical Chemistry, NAWI Graz, Graz University of Technology , Stremayrgasse 9, 8010 Graz, Austria.
authors.forename: Daniela
authors.initials: D
authors.lastname: Hristova-Neeley
authors.affiliation: Institute of Physical and Theoretical Chemistry, NAWI Graz, Graz University of Technology , Stremayrgasse 9, 8010 Graz, Austria.
authors.forename: Dmytro
authors.initials: D
authors.lastname: Neshchadin
authors.affiliation: Institute of Physical and Theoretical Chemistry, NAWI Graz, Graz University of Technology , Stremayrgasse 9, 8010 Graz, Austria.
authors.forename: Georg
authors.initials: G
authors.lastname: Gescheidt