Propagation of Orientation Across Lengthscales in Sheared Self-Assembling Hierarchical Suspensions via Rheo-PLI-SAXS
Journal article, 2025

Simultaneous rheological, polarized light imaging, and small-angle X-ray scattering experiments (Rheo-PLI-SAXS) are developed, thereby providing unprecedented level of insight into the multiscale orientation of hierarchical systems in simple shear. Notably, it is observed that mesoscale alignment in the flow direction does not develop simultaneously across nano-micro lengthscales in sheared suspensions of rod-like chiral-nematic (meso) phase forming cellulose nanocrystals. Rather, with increasing shear rate, orientation is observed first at mesoscale and then extends to the nanoscale, with influencing factors being the aggregation state of the hierarchy and concentration. In biphasic systems, where an isotropic phase co-exists with self-assembled liquid crystalline mesophase domains, the onset of mesodomain alignment towards the flow direction can occur at shear rates nearing one decade before a progressive increase in preferential orientation at nanoscale is detected. If physical confinement prevents the full formation of a cholesteric phase, mesoscale orientation occurs in shear rate ranges that correspond to de-structuring at nanoscale. Interestingly, nano- and mesoscale orientations appear to converge only for biphasic suspensions with primary nanoparticles predominantly made up of individual crystallites and in a high-aspect ratio nematic-forming thin-wall nanotube system. The nano-micro orientation propagation is attributed to differences in the elongation and breakage of mesophase domains.

ForMAX

rheology

orientation

cellulose nanocrystals

small-angle x-ray scattering

hyphenated rheology

combined rheological methods

multiscale analysis

polarized light imaging

MAX IV

CoSAXS

Author

Reza Ghanbari

MAX IV Laboratory

Chalmers, Industrial and Materials Science, Engineering Materials

Ann Terry

Lund Institute of Advanced Neutron and X-ray Science (LINXS)

MAX IV Laboratory

Sylwia Wojno

Wallenberg Wood Science Center (WWSC)

Chalmers, Industrial and Materials Science, Engineering Materials

Marko Bek

Chalmers, Industrial and Materials Science, Engineering Materials

LINXS Inst Adv Neutron & Xray Sci

Kesavan Sekar

Wallenberg Wood Science Center (WWSC)

Chalmers, Industrial and Materials Science, Engineering Materials

Kim Nygård

Lund Institute of Advanced Neutron and X-ray Science (LINXS)

Viney Ghai

Chalmers, Industrial and Materials Science, Engineering Materials

Simona Bianco

University of Glasgow

Marianne Liebi

Chalmers, Physics, Materials Physics

Aleksandar Matic

Chalmers, Physics, Materials Physics

Gunnar Westman

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry

Tiina Nypelö

Lund Institute of Advanced Neutron and X-ray Science (LINXS)

Wallenberg Wood Science Center (WWSC)

Roland Kádár

Wallenberg Wood Science Center (WWSC)

Chalmers, Industrial and Materials Science, Engineering Materials

Lund Institute of Advanced Neutron and X-ray Science (LINXS)

Advanced Science

2198-3844 (ISSN) 21983844 (eISSN)

Vol. 12 7 2410920

Advanced rheometry of CNC based systems

Wallenberg Wood Science Center (WWSC), 2019-01-01 -- 2024-12-31.

2D material-based technology for industrial applications (2D-TECH)

VINNOVA (2019-00068), 2020-05-01 -- 2024-12-31.

GKN Aerospace Sweden (2D-tech), 2021-01-01 -- 2024-12-31.

VINNOVA (2024-03852), 2023-11-01 -- 2029-12-31.

Development of a new rheometer system at MAX IV

MAX IV Laboratory, 2019-03-01 -- 2021-12-31.

The Chalmers University Foundation, 2019-03-01 -- 2021-12-31.

Subject Categories (SSIF 2011)

Other Mechanical Engineering

Other Physics Topics

Nano Technology

Other Materials Engineering

Condensed Matter Physics

Areas of Advance

Nanoscience and Nanotechnology

Materials Science

DOI

10.1002/advs.202410920

More information

Latest update

3/1/2025 4