Paper Number
CS53                         My Program 

Session
Colloidal Suspensions and Granular Materials

Title
Dense Suspensions of Liquid Crystalline "Micro-Potatoes": How Shape Memory Regulates Shear Thickening and Aging

Presentation Date and Time
October 23, 2025 (Thursday) 10:35

Track / Room
Track 1 / Sweeney Ballroom A

Authors (Click on name to view author profile)

  1. Chen, Chuqiao (University of California, Santa Barbara, Chemical Engineering)
  2. Martinez Narváez, Carina D. V. (University of Chicago, Pritzker School of Molecular Engineering)
  3. Rowan, Stuart (University of Chicago, Pritzker School of Molecular Engineering)
  4. de Pablo, Juan (New York University, Tandon School of Engineering)

Author and Affiliation Lines (in printed abstract book)
Chuqiao Chen1, Carina D. V. Martinez Narváez2, Stuart Rowan2 and Juan de Pablo3
1Chemical Engineering, University of California, Santa Barbara, Santa Barbara, CA; 2Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL 60637; 3Tandon School of Engineering, New York University, New York, NY 11201

Speaker / Presenter 
Chen, Chuqiao

Keywords
colloids; field-responsive; gels; non-Newtonian fluids; particualte systems; suspensions

Text of Abstract
Shape anisotropy critically influences inter-particle interactions and the rheological properties of dense suspensions. This work explores the potential of using shape memory particles to dynamically regulate suspension fluid flow through controllable shape transformations. First, liquid crystalline microparticles (“micropotatoes”) characterized by a moderate aspect ratio and high angularity are synthesized. The “micro-potatoes” transform into spheres by heating and reverse to the potato shapes by cooling. The resulting dense suspensions of such particles exhibit strong temperature-dependency in their shear thickening behaviors, spanning discontinuous shear thickening to Newtonian-like rheology at the same volume fraction. Furthermore, we also show that at longer time scales, the suspensions composed of these "micro-potatoes" can undergo physical aging, and evolve into a glassy state. Strikingly, while aging is irreversible with moderate mechanical agitation, triggering the shape memory effect breaks the sticky contacts between particles and leads to nearly full rejuvenation. The findings reported here open up opportunities to leverage ensembles of stimuli-responsive objects for precise control over the collective behavior of a many-body system.