Propagation of Orientation Across Lengthscales in Sheared Self-Assembling Hierarchical Suspensions via Rheo-PLI-SAXS
Journal article, 2024

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.

cellulose nanocrystals

small-angle x-ray scattering

combined rheological methods

polarized light imaging

CoSAXS

orientation

ForMAX

multiscale analysis

rheology

hyphenated rheology

MAX IV

Author

Reza Ghanbari

Chalmers, Industrial and Materials Science, Engineering Materials

MAX IV Laboratory

Ann Terry

MAX IV Laboratory

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

Sylwia Wojno

Chalmers, Industrial and Materials Science, Engineering Materials

Wallenberg Wood Science Center (WWSC)

Marko Bek

LINXS Inst Adv Neutron & Xray Sci

Chalmers, Industrial and Materials Science, Engineering Materials

Kesavan Sekar

Chalmers, Industrial and Materials Science, Engineering Materials

Wallenberg Wood Science Center (WWSC)

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

Wallenberg Wood Science Center (WWSC)

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

Roland Kádár

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

Wallenberg Wood Science Center (WWSC)

Chalmers, Industrial and Materials Science, Engineering Materials

Advanced Science

2198-3844 (ISSN) 21983844 (eISSN)

Vol. In Press

Advanced rheometry of CNC based systems

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

Development of a new rheometer system at MAX IV

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

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

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

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

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

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

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

1/10/2025