Paper Number
SM14                         My Program 

Session
Polymer Solutions, Melts and Blends

Title
Pinching dynamics and extensional rheology of dilute and entangled polymer solutions

Presentation Date and Time
October 20, 2025 (Monday) 4:25

Track / Room
Track 3 / Coronado + DeVargas

Authors (Click on name to view author profile)

  1. Slykas, Cheryl (University of Illinois Chicago, Chemical Engineering)
  2. Martinez Narvaez, Carina (University of Chicago, Pritzker School of Molecular Engineering)
  3. Edano, Louie (University of Illinois Chicago, Chemical Engineering)
  4. Sharma, Vivek (University of Illinois Chicago)

Author and Affiliation Lines (in printed abstract book)
Cheryl Slykas1, Carina Martinez Narvaez2, Louie Edano1 and Vivek Sharma1
1Chemical Engineering, University of Illinois Chicago, Chicago, IL 60707; 2Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL

Speaker / Presenter 
Sharma, Vivek

Keywords
experimental methods; theoretical methods; additve manufacturing; advanced manufacturing; applied rheology; biorheology; flow-induced instabilities; future of rheology; methods; non-Newtonian fluids; polymer blends; polymer solutions; rheometry; sustainability; techniques

Text of Abstract
Concentration-dependent variation of macromolecular conformations and dynamics in polymer solutions are influenced by molecular weight, degree of overlap, solvent quality, persistence length, and number density of entanglements. In this contribution, we characterize the shear and extensional rheology response of flexible and semi-flexible polymer solutions using the broadest range of concentrations, spanning from ultra-dilute to highly entangled using solvent mixtures with varied volatility and solvent quality. We characterize the response to extensional flows realized in capillarity-driven pinching of liquid necks by using the dripping-onto-substrate (DoS) rheometry protocols. The concentration-dependent variation in shear vs extensional rheology response reveals distinct influence of polymer and solvent properties. Lastly, we find standard predictions of FENE-P or Oldroyd-B models are inadequate to describe the observed radius evolution datasets, and yet there are similarities in the response as dictated by dynamics and relaxation of stretched polymers.