The structure of cellulose nanofibril networks at low concentrations and their stabilizing action on colloidal particles

Malin Nordenström; Tobias Benselfelt; Rebecca Hollertz; Stefan Wennmalm; Per A Larsson; Aleksandar Mehandzhiyski; Nicolas Rolland; Igor Zozoulenko; Daniel Söderberg; Lars Wågberg

doi:10.1016/j.carbpol.2022.120046

The structure of cellulose nanofibril networks at low concentrations and their stabilizing action on colloidal particles

Carbohydr Polym. 2022 Dec 1:297:120046. doi: 10.1016/j.carbpol.2022.120046. Epub 2022 Sep 1.

Affiliations

¹ Department of Fiber and Polymer Technology, Division of Fibre Technology, KTH Royal Institute of Technology, Teknikringen 56-58, 100 44 Stockholm, Sweden; Department of Fiber and Polymer Technology, Wallenberg Wood Science Center, KTH Royal Institute of Technology, Teknikringen 56-58, 100 44 Stockholm, Sweden.
² Department of Fiber and Polymer Technology, Division of Fibre Technology, KTH Royal Institute of Technology, Teknikringen 56-58, 100 44 Stockholm, Sweden.
³ Department of Applied Physics, Biophysics, Science for Life Laboratory, KTH Royal Institute of Technology, Tomtebodavägen 23A, 171 65, Solna, Stockholm, Sweden.
⁴ Laboratory of Organic Electronics, Department of Science and Technology, Linköping University, 601 74, Norrköping, Sweden.
⁵ Department of Fiber and Polymer Technology, Wallenberg Wood Science Center, KTH Royal Institute of Technology, Teknikringen 56-58, 100 44 Stockholm, Sweden.
⁶ Department of Fiber and Polymer Technology, Division of Fibre Technology, KTH Royal Institute of Technology, Teknikringen 56-58, 100 44 Stockholm, Sweden; Department of Fiber and Polymer Technology, Wallenberg Wood Science Center, KTH Royal Institute of Technology, Teknikringen 56-58, 100 44 Stockholm, Sweden. Electronic address: wagberg@kth.se.

PMID: 36184183
DOI: 10.1016/j.carbpol.2022.120046

Abstract

The structure and dynamics of networks formed by rod-shaped particles can be indirectly investigated by measuring the diffusion of spherical tracer particles. This method was used to characterize cellulose nanofibril (CNF) networks in both dispersed and arrested states, the results of which were compared with coarse-grained Brownian dynamics simulations. At a CNF concentration of 0.2 wt% a transition was observed where, below this concentration tracer diffusion is governed by the increasing macroscopic viscosity of the dispersion. Above 0.2 wt%, the diffusion of small particles (20-40 nm) remains viscosity controlled, while particles (100-500 nm) become trapped in the CNF network. Sedimentation of silica microparticles (1-5 μm) in CNF dispersions was also determined, showing that sedimentation of larger particles is significantly affected by the presence of CNF. At concentrations of 0.2 wt%, the sedimentation velocity of 5 μm particles was reduced by 99 % compared to pure water.

Keywords: Cellulose nanofibrils; Colloid stability; Diffusion; Models; Sedimentation; Simulations.

MeSH terms

Cellulose* / chemistry
Nanofibers* / chemistry
Silicon Dioxide
Viscosity
Water

Substances

Water
Silicon Dioxide
Cellulose