Contact
    Start Publications Colloidal Ionic Assembly between Anionic Native Cellulose ...
    ←  Publication Finder
    QSense

    Colloidal Ionic Assembly between Anionic Native Cellulose Nanofibrils and Cationic Block Copolymer Micelles into Biomimetic Nanocomposites

    Year: 2011

    Journal: Biomacromolecules, 2011, 12 (6), pp 2074–2081, 20110906

    Authors: Wang M. †, Olszewska A. ‡, Walther A. *†, Malho J-M †, Schacher F.H. §, Ruokolainen J. †, Ankerfors M. #,Laine J. ‡, Berglund L.A., Österberg M. ‡, Ikkala O.*†

    Last authors: Olli Ikkala

    Organizations: †Molecular Materials, Department of Applied Physics and ‡Department of Forest Products Technology, Aalto University (formerly Helsinki University of Technology), FIN-00076 Aalto, Espoo, Finland Laboratory of Organic Chemistry and Macromolecular Chemistry, and Jena Center for Soft Matter, University of Jena, D-07743 Jena, Germany Innventia AB, SE-11486 Stockholm, Sweden Wallenberg Wood Science Center and Department of Fiber and Polymer Technology, Royal Institute of Technology, SE-10044 Stockholm, Sweden

    Country: Finland, Germany, Sweden, Sverige

    We present a facile ionic assembly between fibrillar and spherical colloidal objects toward biomimetic nanocomposites with majority hard and minority soft domains based on anionic reinforcing native cellulose nanofibrils and cationic amphiphilic block copolymer micelles with rubbery core. The concept is based on ionic complexation of carboxymethylated nanofibrillated cellulose (NFC, or also denoted as microfibrillated cellulose, MFC) and micelles formed by aqueous self-assembly of quaternized poly(1,2-butadiene)-block-poly(dimethylaminoethyl methacrylate) with high fraction of the NFC reinforcement. The adsorption of block copolymer micelles onto nanocellulose is shown by quartz crystal microbalance measurements, atomic force microscopy imaging, and fluorescent optical microscopy. The physical properties are elucidated using electron microscopy, thermal analysis, and mechanical testing. The cationic part of the block copolymer serves as a binder to NFC, whereas the hydrophobic rubbery micellar cores are designed to facilitate energy dissipation and nanoscale lubrication between the NFC domains under deformation. We show that the mechanical properties do not follow the rule of mixtures, and synergistic effects are observed with promoted work of fracture in one composition. As the concept allows wide possibilities for tuning, the work suggests pathways for nanocellulose-based biomimetic nanocomposites combining high toughness with stiffness and strength.