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Time-Ionic Strength Superposition: A Unified Description of Chain Relaxation Dynamics in Polyelectrolyte Complexes
Vaqar M S Syed1, Samanvaya Srivastava1
1Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, California 90095, United States.
ACS Macro Letters
|June 1, 2022
Summary
We introduce time-ionic strength superposition (TISS) to unify polyelectrolyte complex (PEC) dynamics. This method accounts for accompanying and added ions, creating a single master curve for PEC viscoelastic response.
Area of Science:
- Polymer Science
- Materials Science
- Physical Chemistry
Background:
- Time-salt superposition (TSS) is established for polyelectrolyte complexes (PECs) but yields distinct master curves at varying initial concentrations.
- Existing TSS methods do not account for accompanying counterions, limiting a unified description of PEC dynamics.
Purpose of the Study:
- To develop a universal description of polyelectrolyte complex (PEC) viscoelastic response.
- To unify distinct time-salt superposition (TSS) master curves using a novel approach.
- To elucidate the role of accompanying counterions in PEC dynamics.
Main Methods:
- Development of the time-ionic strength superposition (TISS) method.
- Assimilation of distinct TSS master curves into a single universal curve.
- Application of a modified sticky Rouse model to describe additional relaxation modes.
Main Results:
- The time-ionic strength superposition (TISS) approach unifies distinct TSS master curves into a single universal curve.
- TISS provides a unified description of PEC viscoelastic response based on solution ionic strength.
- The modified sticky Rouse model quantitatively describes additional relaxation modes influenced by ionic strength.
Conclusions:
- Time-ionic strength superposition (TISS) offers a unified framework for understanding PEC viscoelasticity.
- The study highlights dynamic similarities between PECs and semidilute polymer solutions.
- Ionic strength significantly influences electrostatic screening and chain friction in PEC relaxation dynamics.
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