Paper Number
SC31 

Session
Suspensions and Colloids

Title
Particle-polymer interactions and macromolecular properties of viscoelastic matrix influence the rheology and pinching dynamics of particle suspensions

Presentation Date and Time
October 11, 2022 (Tuesday) 3:45

Track / Room
Track 1 / Sheraton 4

Authors (Click on name to view author profile)

  1. Martinez, Carina (University of Illinois Chicago, Department of Chemical Engineering)
  2. Wang, Chao (PPG Industries, Coatings Application Science)
  3. Sun, Hao (PPG Industries, Coatings Application Science)
  4. Iyer, Divya (University of California Los Angeles, Chemical and Biomolecular Engineering)
  5. Srivastava, Samanvaya (University of California Los Angeles, Chemical and Biomolecular Engineering)
  6. Sharma, Vivek (University of Illinois Chicago, Department of Chemical Engineering)

Author and Affiliation Lines (in printed abstract book)
Carina Martinez1, Chao Wang2, Hao Sun2, Divya Iyer3, Samanvaya Srivastava3 and Vivek Sharma1
1Department of Chemical Engineering, University of Illinois Chicago, Chicago, IL; 2Coatings Application Science, PPG Industries, Allison Park, PA; 3Chemical and Biomolecular Engineering, University of California Los Angeles, Los Angeles, CA

Speaker / Presenter 
Martinez, Carina

Keywords
colloids; polymer solutions; rheometry techniques; suspensions

Text of Abstract
The extensional rheology response of suspensions in viscoelastic fluids and the influence of matrix viscoelasticity on suspended particle dynamics remain less well-understood. Many formulations, including paints, coatings, cosmetics, foodstuff, and biological fluids, form examples of suspensions in viscoelastic fluid. This contribution contrasts the response of particle-laden solutions prepared with colloidal silica particles in two viscoelastic fluid systems based on polyethylene oxide and 2-hydroxyethyl cellulose. A strikingly distinct response was found in both shear and extensional flows characterized using torsional rheometry and capillarity-driven extensional flows using DoS rheometry, respectively. We present the visualization and analysis of pinching dynamics and rheology of particle suspensions, systematically comparing the dilute solution response to existing theoretical models. We elucidate the influence of polymer-particle interactions and macromolecular properties of the suspending fluid on the rheology and pinching dynamics and discuss the implications for dispensing macromolecular complex fluids.