EPR Investigations into the Kinetics of Trithiocarbonate‐Mediated RAFT‐Polymerization of Butyl Acrylate. Issue 18 (25th July 2013)

• Record Type: Journal Article
• Authors: Meiser, Wibke; Buback, Michael; Sidoruk, Alana
• Is Part Of: Macromolecular chemistry and physics. Volume 214:Issue 18(2013:Sep.)
• Page Start: 2108
• Page End: 2114
• Publication Date: 2013-07-25
• Subjects: Polymers -- Periodicals; Polymerization -- Periodicals; Synthetic products -- Periodicals; Macromolecules -- Periodicals; 547.7
• DOI: 10.1002/macp.201300304
• Languages: English
• ISSNs: 1022-1352

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Electron paramagnetic resonance (EPR) spectroscopy is used for measuring rate coefficients of addition, <italic>k</italic><sub>ad</sub>, and fragmentation, <italic>k</italic><sub>β</sub>, together with the associated equilibrium constants, <italic>K</italic><sub>eq</sub>, for butyl acrylate polymerizations mediated by <italic>S</italic>‐ethyl propan‐2‐ylonate‐<italic>S</italic>'‐propyl trithiocarbonate (EPPT) and by <italic>S</italic>‐<italic>S</italic>'‐bis(methyl‐2‐propionate) trithiocarbonate (BMPT). Experiments at −40 °C yield <italic>k</italic><sub>ad</sub> = (3.4 ± 0.3) × 10<sup>6</sup> L mol<sup>−1</sup> s<sup>−1</sup>, <italic>k</italic><sub>β</sub> = (1.4 ± 0.4) × 10<sup>2</sup> s<sup>−1</sup>, and <italic>K</italic><sub>eq</sub> = (2.6 ± 0.8) × 10<sup>4</sup> L mol<sup>−1</sup> for EPPT and <italic>k</italic><sub>ad</sub> = (4.1 ± 0.9) × 10<sup>6</sup> L mol<sup>−1</sup> s<sup>−1</sup>, <italic>k</italic><sub>β</sub> = (4.5 ± 0.5) × 10<sup>1</sup> s<sup>−1</sup>, and <italic>K</italic><sub>eq</sub> = (8 ± 4) × 10<sup>4</sup> L mol<sup>−1</sup> for BMPT. The <italic>K</italic><sub>eq</sub> values are in satisfactory agreement with data from ab initio calculations. <boxed-text content-type="graphic" position="anchor" orientation="portrait"><graphic position="anchor" mimetype="image" xlink:href="ark:/27927/pgg3hsm2cp0" orientation="portrait" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /></boxed-text></p> </abstract>