Paper Number
SC2 

Session
Suspensions & Colloids

Title
The hydrodynamics of the colloidal glass transition

Presentation Date and Time
October 15, 2018 (Monday) 10:15

Track / Room
Track 1 / Galleria I

Authors (Click on name to view author profile)

  1. Zia, Roseanna N. (Stanford University, Chemical Engineering)
  2. Wang, Jialun (Stanford University, Chemical Engineering)
  3. McKenna, Gregory B. (Texas Tech University, Department of Chemical Engineering)
  4. Peng, Xiaoguang (University of Connecticut, Chemical & Biomolecular Engineering)
  5. Li, Qi (Texas Tech University, Chemical Engineering)

Author and Affiliation Lines (in printed abstract book)
Roseanna N. Zia1, Jialun Wang1, Gregory B. McKenna2, Xiaoguang Peng2, and Qi Li2
1Chemical Engineering, Stanford University, Stanford, CA, CA 94305-4125; 2Department of Chemical Engineering, Texas Tech University, Lubbock, TX 79409

Speaker / Presenter 
Zia, Roseanna N.

Text of Abstract
We study via large-scale Stokesian dynamics simulation the colloidal glass transition and subsequent structural relaxation, utilizing controlled jumps from the liquid state into the putative glass region. We execute such volume-fraction jumps with a range of quench depths and quench rates, where particle size increases at constant system volume. Here we focus on the effects of particle softness as well as lubrication and many-body long-range hydrodynamic interactions on post-jump particle dynamics, where we implement the protocols of the Kovacs signature experiments (intrinsic isovolume-fraction) to study the approach to a stationary state. The results are compared with light scattering and rheology experiments. The system takes a finite time to reach a metastable intransient state at the widely-accepted colloidal glass transition point, volume fraction 58%, challenging prior assertions that particle dynamics vanish at the glass transition. The exploration of even deeper quenches (higher final volume fractions) up to the random close packing reveals interesting convolution between aging and lag-time dynamics. Detailed study of structural and rheological evolution after the jump are utilized to elucidate the mechanistic process of glassy arrest.