One-dimensional optical reflectors based on self-organization of polymeric comb-shaped supramoleculesH. Kosonen1, 2, S. Valkama1, J. Ruokolainen1, 3, M. Torkkeli4, R. Serimaa4, G. ten Brinke1, 5 and O. Ikkala1
1 Department of Engineering Physics and Mathematics and Center for New Materials, Helsinki University of Technology, PO Box 2200, FIN-02015 HUT, Espoo, Finland
2 VTT Microelectronics, Technical Research Centre of Finland, PO Box 1208, FIN-02044 VIT, Finland
3 Department of Materials, University of California Santa Barbara, Santa Barbara, CA 93106 USA
4 Department of Physical Sciences, University of Helsinki, PO Box 64, FIN-00014 Helsinki, Finland
5 Laboratory of Polymer Chemistry, Dutch Polymer Institute, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands
(Received 30 April 2002 Published online: 11 March 2003 )
We demonstrate that complexation of dodecylbenzenesulphonic acid, DBSA, to a diblock copolymer of polystyrene-block-poly(4-vinylpyridine), PS-block-P4VP, leads to polymeric supramolecules PS-block-P4VP(DBSA) y ( y = 1.0, 1.5, and 2.0), which self-organize with a particularly large lamellar periodicity in excess of 1000 Å. The structures consist of alternating PS and P4VP(DBSA) y layers, where the latter contains smaller internal structure, probably lamellar. The DBSA side chains are bonded to the pyridines by protonation and hydrogen bonding and they effectively plasticize the material. In this way relatively well-developed structures are obtained even without annealing or macroscopic alignment. Transmission and reflectance measurements show that a relatively narrow and incomplete bandgap exists for supramolecules of high molecular weight block copolymer at ca. 460 nm.
42.70.Qs - Photonic bandgap materials.
83.70.Hq - Heterogeneous liquids: suspensions, dispersions, emulsions, pastes, slurries, foams, block copolymers, etc..
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2003