Advertisement

Increasing the Isomerisation Kinetics of Azo Dyes by Chemical Bonding to Liquid-Crystalline Polymers

Authors

  • Jaume Garcia-Amorós,

    1. Departament de Química Orgànica, Institut de Nanociència i Nanotecnologia, Universitat de Barcelona, Martí i Franqués 1-11, 08028 Barcelona (Spain), Fax: (+34) 93-339-78-78
    Search for more papers by this author
  • Prof. Dr. Heino Finkelmann,

    Corresponding author
    1. Institut für Makromolekulare Chemie, Hermann-Staudinger Haus, Albert-Ludwigs-Universität Freiburg, Stefan-Meier Strasse 31, 79104 Freiburg im Breisgau (Germany)
    • Institut für Makromolekulare Chemie, Hermann-Staudinger Haus, Albert-Ludwigs-Universität Freiburg, Stefan-Meier Strasse 31, 79104 Freiburg im Breisgau (Germany)
    Search for more papers by this author
  • Dr. Dolores Velasco

    Corresponding author
    1. Departament de Química Orgànica, Institut de Nanociència i Nanotecnologia, Universitat de Barcelona, Martí i Franqués 1-11, 08028 Barcelona (Spain), Fax: (+34) 93-339-78-78
    • Departament de Química Orgànica, Institut de Nanociència i Nanotecnologia, Universitat de Barcelona, Martí i Franqués 1-11, 08028 Barcelona (Spain), Fax: (+34) 93-339-78-78
    Search for more papers by this author

Abstract

It is well known that the proper substitution of the azobenzene core allows tuning the thermal cis-to-trans isomerisation kinetics of azo dyes. The thermal isomerisation process of nitro-substituted azobenzenes is accelerated up to 13 times with respect to that in the common isotropic solvents when they are doped in nematic low molar mass liquid crystals. This kinetic acceleration is even stronger when these azo dyes are covalently linked to a nematic siloxane polymer. In this environment, the isomerisation process is accelerated more than 103 times. This effect is presented herein for the first time. The possible application of the networks obtained as possible photo-actuators has been also considered.

Ancillary