Electron spin resonance studies of reversible addition-fragmentation transfer polymerisation

Date
2003
Authors
Calitz F.M.
Tonge M.P.
Sanderson R.D.
Journal Title
Journal ISSN
Volume Title
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Abstract
The polymerisation of styrene in the presence of cumyl dithiobenzoate (RAFT agent) was studied. Electron spin resonance spectroscopy was used to determine the time-dependence of the concentrations of the intermediate radical species, as a function of temperature and relative initial amounts of reactants. The intermediate radical concentration was found to be much lower than predicted by the studies of Barner-Kowollik et al. [Barner-Kowollik, C.; Quinn, J. F.; Morsley, D. R.; Davis, T. P. J. Polym. Sci. Part A: Polym. Chem. 2001, 39, 1353], but consistent with that observed by Hawthorne et al. [Hawthorne, D. G.; Moad, G.; Rizzardo, E.; Thang, S. H. Macromolecules 1999, 32, 5457] and Kwak et al. [Kwak, Y.; Goto, A.; Tsuji.; Murata, Y.; Komatsu, K.; Fukuda, T. Macromolecules 2002, 35, 3026] Several observations that are not consistent with the current RAFT model were made. Intermediate radical signals were observed long after a significant amount of initiator remained and an extra signal appeared in the ESR spectrum at longer reaction times.
Description
Keywords
Free radical polymerization, Initiators (chemical), Macromolecules, Paramagnetic resonance, Spectrum analysis, Intermediate radical species, Styrene, benzoic acid derivative, cumyl dithiobenzoate, radical, styrene, unclassified drug, chemical reaction, chemical structure, conference paper, electron spin resonance, kinetics, polymerization, reaction time, temperature, time
Citation
Macromolecular Symposia
193