Effect of Isopropanol Cosolvent on the Rheology and Spinnability of Aqueous Polyacrylic Acid Solutions

Sunilkumar Khandavalli, Yingying Chen, Nisha Sharma-Nene, Kashyap Rajan, Samrat Sur, Jonathan Rothstein, Kimberley Reeves, David Cullen, Kenneth Neyerlin, Scott Mauger, Michael Ulsh

Research output: Contribution to journalArticlepeer-review


We investigate the effect of alcohol fraction (isopropanol, IPA) in a binary water-alcohol solvent mixture on the shear and extensional rheological properties, as well as the role of viscoelasticity on fiber formation of poly(acrylic acid) (PAA) in electrospinning. Comparison of the scaling of both specific viscosities ηsp and extensional relaxation times λE of PAA in water–IPA mixtures, showed stronger scaling compared to salt-free aqueous polyelectrolyte solutions, except for the ηsp in the unentangled regime displaying a polyelectrolyte-like scaling ηsp ~ c0.5 for all IPA%. Such deviation suggested IPA induces association/aggregation of PAA. However, the trends between ηsp and λE magnitudes as a function of IPA% differ for concentrations compared in the entangled regime. The ηsp as well as their elastic moduli exhibit a maximum, whereas λE increases monotonically with IPA%, suggesting a complex interplay of various interactions are dictating their structure in water-IPA mixtures, affecting their shear and extensional response differently. Electrospinning experiments showed increasing IPA% reduces the onset of both beaded and uniform fibers. Analysis using dimensionless numbers indicated the enhancement of their elasticity by IPA, and the consequent stabilizing effect on their jets/filaments against break-up during electrospinning, plays a role in the improvement of their fiber formation.

Original languageAmerican English
Pages (from-to)1495-1512
Number of pages18
JournalJournal of Polymer Science
Issue number14
StatePublished - 2023

Bibliographical note

Publisher Copyright:
© 2023 Alliance for Sustainable Energy, LLC and Oak Ridge National Laboratory and The Authors. Journal of Polymer Science published by Wiley Periodicals LLC.

NREL Publication Number

  • NREL/JA-5K00-84762


  • electrospinning
  • extensional rheology
  • nanofibers
  • polyacrylic acid
  • polyelectrolytes
  • shear rheology


Dive into the research topics of 'Effect of Isopropanol Cosolvent on the Rheology and Spinnability of Aqueous Polyacrylic Acid Solutions'. Together they form a unique fingerprint.

Cite this