Synthesis of star polymers via nitroxide mediated free-radical polymerization: A “core-first” approach using resorcinarene-based alkoxyamine initiators

다국어 초록 (Multilingual Abstract)

<P>The synthesis of new octafunctional alkoxyamine initiators for nitroxide-mediated radical polymerization (NMRP), by the derivatization of resorcinarene with nitroxide free radicals viz TEMPO and a freshly prepared phosphonylated nitroxide, is described. The efficiency of these initiators toward the controlled radical polymerization of styrene and tert-butyl acrylate is investigated in detail. Linear analogues of these multifunctional initiators were also prepared to compare and evaluate their initiation efficiency. The favorable conditions for polymerization were optimized by varying the concentration of initiators and free nitroxides, reaction conditions, etc., to obtain well-defined star polymers. Star polystyrene thus obtained were further used as macro-initiator for the block copolymerization with tert-butyl acrylate. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5559–5572, 2007</P>
<B>Graphic Abstract</B>
<P>The synthesis of new octafunctional alkoxyamine initiators for nitroxide-mediated radical polymerization (NMRP), by the derivatization of resorcinarene with nitroxide free radicals viz TEMPO and a freshly prepared phosphonylated nitroxide, is described. The efficiency of these initiators towards the controlled radical polymerization of styrene and tert-butyl acrylate is investigated in detail. Linear analogues were also prepared to compare the initiation efficiency. The favorable conditions for polymerization were optimized by varying reaction parameters, to obtain well-defined star polymers. Star polystyrene thus obtained were further used as macroinitiator for the block copolymerization with tert-butyl acrylate. [Color figure can be viewed in the online issue, which is available at www.interscience.wiley.com.]</P><P>
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