Multiscale flow alignment in cellulose nanocrystals controlled by surface topology
Journal article, 2026
We address how surface topology controls the multiscale flow alignment of cellulose nanocrystal (CNC) suspensions using a single in-situ experiment that combines rheology, polarized light imaging (PLI), and small-angle X-ray scattering (SAXS). Across a series of azetidinium-based dialkyl linker topologies, we resolve the propagation of alignment from the mesoscale (PLI) to the nanoscale (SAXS). While pristine CNC suspensions exhibit nearly-simultaneous onset of mesoscale birefringence and nanoscale alignment, surface-modified systems show a pronounced decoupling between these processes. In particular, the appearance of the Maltese-cross pattern in PLI systematically precedes detectable nanoscale alignment in SAXS. This is strongly dependent on linker topology. Extending the analysis beyond the Hermans parameter, S2, to higher-order anisotropy parameters and benchmarking their evolution against a generalized Maier-Saupe-type anisotropy distribution function, we show that higher-order anisotropy parameters qualitatively distinguish alignment regimes that are indistinguishable from S2 alone. The work establishes linker topology as a controlling variable for multiscale flow alignment in CNC systems and highlights the higher-order character of their alignment behavior.
Surface linkers
Rheology
Small-angle x-ray scattering
Azedidinium salts
Cellulose nanocrystals
Polarized light imaging
Author
Ases Akas Mishra
Chalmers, Industrial and Materials Science, Engineering Materials
Amit Kumar Sonker
Chalmers, Industrial and Materials Science, Engineering Materials
Technical Research Centre of Finland (VTT)
Kesavan Sekar
Chalmers, Industrial and Materials Science, Engineering Materials
Marko Bek
MAX IV Laboratory
Chalmers, Industrial and Materials Science, Engineering Materials
Lund Institute of Advanced Neutron and X-ray Science (LINXS)
Ann Terry
Lund Institute of Advanced Neutron and X-ray Science (LINXS)
MAX IV Laboratory
Kim Nygård
Lund Institute of Advanced Neutron and X-ray Science (LINXS)
MAX IV Laboratory
Stuart Ansell
MAX IV Laboratory
Lund Institute of Advanced Neutron and X-ray Science (LINXS)
Gunnar Westman
Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry
Roland Kádár
Computational Mechanics and Materials Engineering
Lund Institute of Advanced Neutron and X-ray Science (LINXS)
MAX IV Laboratory
Journal of Colloid and Interface Science
00219797 (ISSN) 10957103 (eISSN)
Vol. 723 140913Areas of Advance
Nanoscience and Nanotechnology
Production
Materials Science
Subject Categories (SSIF 2025)
Condensed Matter Physics
Other Physics Topics
Physical Chemistry
DOI
10.1016/j.jcis.2026.140913
PubMed
42341728