Reversible addition - Fragmentation chain transfer polymerization initiated with ultraviolet radiation

John F. Quinn, Leonie Barner, Christopher Barner-Kowollik, Ezio Rizzardo, Thomas P. Davis

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237 Citations (Scopus)


Styrene was polymerized under a source of ultraviolet radiation in the presence of certain thiocarbonylthio compounds. Use of 1-phenylethyl phenyldithioacetate (1-PEPDTA) produced well-defined polymers with molecular weights close to those predicted from theory, up to conversions of 30%. The mechanism of polymerization was examined and shown to proceed via reversible addition-fragmentation chain transfer, as opposed to reversible termination with a thiocarbonylthiyl radical. U-V-induced decomposition of the dithioester moiety in 1-PEPDTA and 1-phenylethyl dithiobenzoate (1-PEDB) mediated RAFT polymerizations was followed using UV/vis spectrophotometry; 1-PEPDTA decomposed much slower than 1-PEDB. Analysis of the decomposition products of 1-PEPDTA with gas chromatography/mass spectrometry was used to elucidate a possible mechanism for its degradation, suggesting that both 1-phenylethyl and benzyl radicals are decomposition products.

Original languageEnglish
Pages (from-to)7620-7627
Number of pages8
Issue number20
Publication statusPublished - 24 Sep 2002
Externally publishedYes

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