Get access

Reversible addition fragmentation chain transfer polymerization of sterically hindered monomers: Toward well-defined rod/coil architectures

Authors

  • Zachary Szablan,

    1. Centre for Advanced Macromolecular Design, School of Chemical Engineering and Industrial Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
    Search for more papers by this author
  • Andrew Ah Toy,

    1. Centre for Advanced Macromolecular Design, School of Chemical Engineering and Industrial Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
    Search for more papers by this author
  • Thomas P. Davis,

    1. Centre for Advanced Macromolecular Design, School of Chemical Engineering and Industrial Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
    Search for more papers by this author
  • Xiaojuan Hao,

    1. Centre for Advanced Macromolecular Design, School of Chemical Engineering and Industrial Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
    Search for more papers by this author
  • Martina H. Stenzel,

    1. Centre for Advanced Macromolecular Design, School of Chemical Engineering and Industrial Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
    Search for more papers by this author
  • Christopher Barner-Kowollik

    Corresponding author
    1. Centre for Advanced Macromolecular Design, School of Chemical Engineering and Industrial Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
    • Centre for Advanced Macromolecular Design, School of Chemical Engineering and Industrial Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia
    Search for more papers by this author

Abstract

The sterically hindered monomers dibutyl itaconate (DBI) and dicyclohexyl itaconate (DCHI) were polymerized via reversible addition fragmentation chain transfer (RAFT) free-radical polymerization. S,S′-Bis(α,α′-dimethyl-α″-acetic acid) trithiocarbonate, cumyl dithiobenzoate, and cumyl phenyldithioacetate have been used as RAFT agents to mediate a series of polymerizations at 65 °C yielding rod polymers ranging in number average molecular weight from 9000 to 92,000 g mol−1. The progress of the polymerization was followed via online Fourier transform–near infrared spectroscopy. The polydispersity indices of the obtained rod polymers were relatively high at 1.4–1.7. The RAFT polymerizations of the hindered monomers used in the present study displayed both ideal living and hybrid behavior between conventional and living polymerization, depending on the RAFT agent used. DCHI rod polymers generated via the RAFT process were subsequently reinitiated in the presence of styrene to produce a range of BAAB and A-B rod-coil block copolymers of molecular weights up to 164,000 g mol−1. The chain extension yields molecular weight distributions that progressively shift to higher molecular weights and are unimodal. Thermogravimetric analysis of the pDCHI-block-pStyrene copolymers indicates thermal degradation in two separate steps for the pDCHI and pStyrene blocks. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2432–2443, 2004

Ancillary