Advanced Functional Materials

Cover image for Advanced Functional Materials

September, 2003

Volume 13, Issue 9

Pages 663–742

    1. Contents: Adv. Funct. Mater. 9/2003 (pages 663–665)

      Article first published online: 1 SEP 2003 | DOI: 10.1002/adfm.200390048

    2. Patterning of Gold Substrates by Surface-Initiated Polymerization (pages 667–670)

      D.J. Dyer

      Article first published online: 1 SEP 2003 | DOI: 10.1002/adfm.200301007

      The design and synthesis of durable and functional organic coatings is an important topic in contemporary polymer science. The well-defined patterning of inorganic substrates is highlighted with an emphasis on planar gold. New advances in contact printing and surface initiated polymerization promise unprecedented control of the polymer architecture in the micrometer and nanometer range.

    3. Structural and Spectroscopic Studies on Mesoporous Tantalum Oxide–Sodium Fulleride Composites with Conducting Fulleride Columns in the Pores (pages 671–681)

      B.O. Skadtchenko, M. Trudeau, R.W. Schurko, M.J. Willans and D. Antonelli

      Article first published online: 1 SEP 2003 | DOI: 10.1002/adfm.200304392

      Mesoporous Ta oxide Na fulleride composites (see Figure) have been synthesized by solution impregnation and spectroscopically characterized as a function of their Na loading. The materials show very different electronic properties from the bulk, and NMR results suggest a new fullerene structural type in which anionic C60 columns are enclosed in a double sheath of Na cations and the walls of the mesopores (see inside cover).

    4. Synthesis of New Europium Complexes and Their Application in Electroluminescent Devices (pages 683–691)

      P.P. Sun, J.P. Duan, J.J. Lih and C.H. Cheng

      Article first published online: 1 SEP 2003 | DOI: 10.1002/adfm.200304378

      A series of europium complexes utilizing a substituted phenanthroline as ligand have been synthesized (see Figure for an example). Several of these europium complexes were used as emitting red dopants in organic electroluminescent devices and they appear to be the only few europium complexes that show maximum brightnesses of more than 1000 cd m–2 when used as dopants in this way.

    5. Functionalization of Poly(ethylene terephthalate) Film by Pulsed Plasma Deposition of Maleic Anhydride (pages 692–697)

      J. Hu, C. Yin, H.-Q. Mao, K. Tamada and W. Knoll

      Article first published online: 1 SEP 2003 | DOI: 10.1002/adfm.200304384

      Poly(ethylene terephthalate) films have been functionalized with carboxyl groups by pulsed plasma polymerization of maleic anhydride. The preserved anhydride groups of MA were converted to carboxyl groups by subsequent hydrolysis. The coverage of the PET surface with plasma polymers (see Figure) and the persistence of functional groups after water treatment of the processed PET substrate were observed.

    6. Block Copolymer Surface Reconstuction: A Reversible Route to Nanoporous Films (pages 698–702)

      T. Xu, J. Stevens, J.A. Villa, J.T. Goldbach, K.W. Guarini, C.T. Black, C.J. Hawker and T.P. Russell

      Article first published online: 1 SEP 2003 | DOI: 10.1002/adfm.200304374

      A nanoporous template is produced from a block copolymer film of polystyrene (PS) with cylindrical phases of poly(methyl methacrylate) (PMMA). Exposure to acetic acid and drying results in cylindrical holes in the PS film (see Figure), thought to result from migration of the PMMA to the surface. Template formation is reversible, in that on annealing above the glass-transition temperature, the initial film morphology is restored.

    7. High-Performance, Monolithic Polyaniline Electrochemical Actuators (pages 703–709)

      J.-M. Sansiñena, J. Gao and H.-L. Wang

      Article first published online: 1 SEP 2003 | DOI: 10.1002/adfm.200304347

      Monolithic electrochemical actuators based on a single polyaniline (PANI) asymmetric membrane have been constructed, and a bending movement of up to 20 Hz has been experimentally recorded in a 1 M hydrochloric acid aqueous solution (see Figure, showing deformation under ± 2 V). Furthermore, a lifetime of over 329 500 cycles was determined for these actuators at a ± 2° angular displacement (5 Hz).

    8. Nanocomposite Electrolytes with Fumed Silica and Hectorite Clay Networks: Passive versus Active Fillers (pages 710–717)

      H.J. Walls, M.W. Riley, R.R. Singhal, R.J. Spontak, P.S. Fedkiw and S.A. Khan

      Article first published online: 1 SEP 2003 | DOI: 10.1002/adfm.200304333

      A passive filler, hydrophobic fumed silica (see Figure, left), and an active filler, lithium-exchanged hectorite (Figure, right), are compared for use in nanocomposite electrolytes for rechargeable Li batteries. With the former, mechanical and electrical properties are decoupled, whereas with the latter, these properties are coupled. Both fillers self-assemble within the nanocomposite to form an interconnected network that provides structural strength.

    9. Assembly of Photopolymerizable Discotic Molecules on an Aligned Polyimide Layer Surface to Form a Negative Retardation Film with an Oblique Optical Axis (pages 718–725)

      J.J. Ge, S.-C. Hong, B.Y. Tang, C.Y. Li, D. Zhang, F. Bai, B. Mansdorf, F.W. Harris, D. Yang, Y.-R. Shen and S.Z.D. Cheng

      Article first published online: 1 SEP 2003 | DOI: 10.1002/adfm.200304365

      Negative compensation films with an oblique optical axis have been developed using ultraviolet polymerizable discotic liquid-crystalline molecules (see Structure) assembled on a specifically designed rubbing-aligned polyimide layer surface. Results of surface-sensitive techniques indicate that rubbing causes the polyimide surface structural re-arrangement resulting in a negative pre-tilt angle. The optical properties of this film were confirmed by an optical model calculation.

    10. A Highly Stable, New Electrochromic Polymer: Poly(1,4-bis(2-(3′,4′-ethylenedioxy) thienyl)-2-methoxy-5-2″-ethylhexyloxybenzene) (pages 726–731)

      G. Sonmez, H. Meng, Q. Zhang and F. Wudl

      Article first published online: 1 SEP 2003 | DOI: 10.1002/adfm.200304317

      P(BEDOT-MEHB) is synthesized and its electrochemical and electrochromic properties reported (P(BEDOT-MEHB) = poly(1,4-bis(2-(3′,4′-ethylenedioxy)thienyl)-2-methoxy-5-2″-ethylhexyloxybenzene)). P(BEDOT-MEHB) shows a very well defined electrochemistry, high stability to over-oxidation, and a relatively low oxidation potential of the monomer (+ 0.44 V vs. Ag/Ag+, see Figure).

    11. Photoreplicated Anisotropic Liquid-Crystalline Lenses for Aberration Control and Dual-Layer Readout of Optical Discs (pages 732–738)

      H.R. Stapert, S. del Valle, E.J.K. Verstegen, B.M.I. van der Zande, J. Lub and S. Stallinga

      Article first published online: 1 SEP 2003 | DOI: 10.1002/adfm.200304385

      Increase in optical storage capacity can be obtained by increasing the number of information layers per disc. The 25 μm thick spacer in dual-layer Blu-Ray Discs introduces a 255 mλ root-mean-square spherical aberration, which must be compensated. To enable dual-layer readout, we have developed birefringent lenses (see Figure) and a light path for optical readout (see cover). We report on the liquid-crystal material properties and the photoreplication for the production of birefringent lenses.