| Abstract
| - The atom transfer radical copolymerization (ATRP) of methyl acrylate (MA) with 1-octenewas investigated in detail. Well-controlled copolymers containing almost 25 mol % of 1-octene wereobtained using ethyl 2-bromoisobutyrate (EBriB) as initiator. Narrow molar mass distributions (MMD)were obtained for the ATRP experiments. The feasibility of the ATRP copolymerizations was independentof the ligand employed. Copolymerizations carried out using 4,4‘-dinonyl-2,2‘-bipyridine (dNbpy) resultedin good control, with significant octene incorporation in the polymer. The lower overall percent conversionobtained for the dNbpy systems as compared to that of the PMDETA systems was attributed to the redoxpotential of the formed copper(I)−ligand complex. The comparable free radical (co)polymerizations (FRP)resulted in broad MMD. An increase in the fraction of the olefin in the monomer feed led to an increasein the level of incorporation of the olefin in the copolymer, at the expense of the overall percent conversion.There was a good agreement between the values of the reactivity ratios determined for the ATRP andFRP systems. The formation of the copolymer was established using matrix-assisted laser desorption/ionization−time-of-flight−mass spectrometry (MALDI−TOF−MS). From the obtained MALDI−TOF−MS spectra for the ATRP systems, several units of 1-octene were incorporated in the polymer chain, andonly one pair of end groups was observed. On comparison, in the FRP systems, due to the multitude ofside reactions occurring, several end groups were obtained. In general, narrow chemical compositiondistributions were obtained for the ATRP systems as compared to FRP.
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