• Title of article

    Well-defined poly(dimethylsiloxane)-b-poly(2,2,3,3,4,4,4-heptafluorobutylmethacryl-ate-b-poly(styrene) (PDMS-b-PHFBMA-b-PS) triblock copolymers were prepared by two-step reversible addition–fragmentation chain transfer (RAFT) polymerization. A comprehensi

  • Author/Authors

    Mazhar Iqbal، نويسنده , , Theo J. Dingemans، نويسنده ,

  • Issue Information
    روزنامه با شماره پیاپی سال 2010
  • Pages
    7
  • From page
    2174
  • To page
    2180
  • Abstract
    In this paper the synthesis and characterization of a new family reactive nematic oligomers based on 4-hydroxybenzoic acid (4-HBA) will be presented. We modified the backbone using para- and meta-substituted aromatic monomers such as terephthalic acid (TA), isophthalic acid (IA), hydroquinone (HQ), resorcinol (RS), 4,4′-bisphenol (BP) and 3-hydroxybenzoic acid (3-HBA). All oligomers, with a target Mn of 5000 and 9000 g mol−1, were end-capped with reactive phenylethynyl functionalities and synthesized using standard melt condensation techniques. Curing of the phenylethynyl reactive functionalities proceeds through chain extension and crosslinking, depending upon the temperature and time and can be carried out between 310 and 400 °C. Fully cured nematic thermosets could be obtained with glass-transition temperatures previously not accessible (Tg > 400 °C). The cured polymers exhibit excellent tensile properties, i.e. tensile strength (83 MPa) and elongation at break (9%). This approach allows us to prepare all-aromatic polymers with a combination of useful properties such as ease of processing, high Tg’s, and excellent mechanical properties.
  • Keywords
    thermosets , Glass-transition temperature , Liquid crystal , Reactive oligomers , mechanical properties
  • Journal title
    European Polymer Journal(EPJ)
  • Serial Year
    2010
  • Journal title
    European Polymer Journal(EPJ)
  • Record number

    1228538