NMR studies on the mechanism of reverse iodine transfer polymerization of styrene

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dc.contributor.authorWright T.
dc.contributor.authorChirowodza H.
dc.contributor.authorPasch H.
dc.date.accessioned2012-05-17T08:58:56Z
dc.date.available2012-05-17T08:58:56Z
dc.date.issued2012
dc.description.abstractThe evolution of chain transfer agents (CTAs) was studied for the polymerization of styrene by reverse iodine transfer polymerization (RITP). CTAs are formed during an inhibition period where the radical initiator reacts with molecular iondine. These compounds were studied using in situ 1H nuclear magnetic resonance (NMR) experiments. The molecular weight of polystyrene was evaluated with size exclusion chromatography (SEC) and 1H NMR. Structural analysis of the resulting polymers was done using 1H NMR spectroscopy and matrix-assisted laser desorption/ionization time-of-flight (MALDI-ToF) mass spectrometry. The inhibition period of styrene polymerized by RITP was much shorter than expected. This is due to the consumption of iodine in the reaction between styrene and iodine which reversibly forms 1,2-diiodoethylbenzene leading to the subsequent formation of 1-phenylethyl iodide (1-PEI). For the first time the formation of 1,2-diiodoethylbenzene as an intermediate structure in RITP of styrene has been proven experimentally. The active role of 1-PEI in the polymerization process is documented through the detection of phenylethyl end groups by MALDI-ToF and 1H NMR. © 2012 American Chemical Society.
dc.identifier.citationMacromolecules
dc.identifier.citation45
dc.identifier.citation7
dc.identifier.citation2995
dc.identifier.citation3003
dc.identifier.issn249297
dc.identifier.other10.1021/ma3003888
dc.identifier.urihttp://hdl.handle.net/10019.1/21027
dc.subjectChain transfer agents
dc.subjectEnd groups
dc.subjectH NMR spectroscopy
dc.subjectIn-situ
dc.subjectIntermediate structures
dc.subjectMALDI-TOF
dc.subjectMatrix-assisted laser desorption/ionization time-of-flight
dc.subjectNMR studies
dc.subjectPolymerization process
dc.subjectRadical initiators
dc.subjectTransfer polymerization
dc.subjectIodine
dc.subjectMass spectrometry
dc.subjectPolymerization
dc.subjectPolymers
dc.subjectPolystyrenes
dc.subjectStyrene
dc.subjectAtom transfer radical polymerization
dc.titleNMR studies on the mechanism of reverse iodine transfer polymerization of styrene
dc.typeArticle
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