title: Hydrodynamic alignment and assembly of nanofibrils resulting in strong cellulose filaments.
abstract: Cellulose nanofibrils can be obtained from trees and have considerable potential as a building block for biobased materials. In order to achieve good properties of these materials, the nanostructure must be controlled. Here we present a process combining hydrodynamic alignment with a dispersion-gel transition that produces homogeneous and smooth filaments from a low-concentration dispersion of cellulose nanofibrils in water. The preferential fibril orientation along the filament direction can be controlled by the process parameters. The specific ultimate strength is considerably higher than previously reported filaments made of cellulose nanofibrils. The strength is even in line with the strongest cellulose pulp fibres extracted from wood with the same degree of fibril alignment. Successful nanoscale alignment before gelation demands a proper separation of the timescales involved. Somewhat surprisingly, the device must not be too small if this is to be achieved.
authors.affiliation: 1] Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden [2] Linné FLOW Centre, KTH Mechanics, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden.
authors.forename: Karl M O
authors.initials: KM
authors.lastname: Håkansson
authors.affiliation: 1] Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden [2] Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden.
authors.forename: Andreas B
authors.initials: AB
authors.lastname: Fall
authors.affiliation: 1] Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden [2] Linné FLOW Centre, KTH Mechanics, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden.
authors.forename: Fredrik
authors.initials: F
authors.lastname: Lundell
authors.affiliation: Photon Science, DESY, Notkestrasse 85, Hamburg D-22607, Germany.
authors.forename: Shun
authors.initials: S
authors.lastname: Yu
authors.affiliation: 1] Ruprecht Haensel Laboratory, University of Kiel, Kiel D-24098, Germany [2] Helmholtz-Zentrum Geesthacht, Institute for Materials Research, Geesthacht D-21502, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Krywka
authors.affiliation: Photon Science, DESY, Notkestrasse 85, Hamburg D-22607, Germany.
authors.forename: Stephan V
authors.initials: SV
authors.lastname: Roth
authors.affiliation: Photon Science, DESY, Notkestrasse 85, Hamburg D-22607, Germany.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Santoro
authors.affiliation: 1] Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden [2] Linné FLOW Centre, KTH Mechanics, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden.
authors.forename: Mathias
authors.initials: M
authors.lastname: Kvick
authors.affiliation: 1] Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden [2] Linné FLOW Centre, KTH Mechanics, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden.
authors.forename: Lisa
authors.initials: L
authors.lastname: Prahl Wittberg
authors.affiliation: 1] Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden [2] Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden.
authors.forename: Lars
authors.initials: L
authors.lastname: Wågberg
authors.affiliation: 1] Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden [2] Linné FLOW Centre, KTH Mechanics, KTH Royal Institute of Technology, Stockholm SE-100 44, Sweden [3] Innventia AB, PO Box 5604, Stockholm SE-114 86, Sweden.
authors.forename: L Daniel
authors.initials: LD
authors.lastname: Söderberg
mesh_terms: D001672:Biocompatible Materials; D002482:Cellulose; D057446:Hydrodynamics; D057139:Nanofibers; D049329:Nanostructures; D014867:Water; D014934:Wood
chemical_list: D001672:Biocompatible Materials; D014867:Water; D002482:Cellulose