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Reaction of oligoalcohols with diepoxides: An easy,one‐pot way to star‐shaped,multibranched polymers. II. Poly(ethylene oxide) stars—synthesis and analysis by size exclusion chromatography triple‐detection method
Authors:Grzegorz Lapienis  Stanislaw Penczek
Abstract:An Erratum has been published for this article in Journal of Polymer Science Part A: Polymer Chemistry (2004) 42(10) 2575‐2576 Starlike, highly branched (AxByAz) macromolecules having from a few to 100 arms and molar masses up to 105 were prepared in three stages with the one‐pot, arms‐core‐arms method (By stands for y molcules of former diepoxides introduced into the core). Oligoalcohols, at least partially converted into their alcoholate counterpart states, reacted with diepoxy compounds giving star‐shaped, highly branched macromolecules. With the properly chosen conditions, complete conversion of both starting components was achieved. In this article homostars built with the first and second generation of poly(ethylene oxide) arms (Ax and Az, respectively) are described. The number of arms (f) was determined either by direct measurements of the number‐average molcular weight (Mn) of the first and second stars (Mn of arms Ax and Az is known) or by calculating f from branching indices g and g′ determined from the radius of gyration and the limited viscosity number measured with size exclusion chromatography (SEC) triple detection with TriSEC software. For a few samples, Mn was measured with high‐speed membrane osmometry. The progress of the stars' formation was monitored by 1H NMR, SEC, and matrix‐assisted laser desorption/ionization time‐of‐flight methods. Functionalization of the ? OH end groups in the second generation of arms was observed by 1H and/or 31P NMR. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1576–1598, 2004
Keywords:anionic polymerization  star polymers  polyethers  size exclusion chromatography (SEC)  MALDI  NMR
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