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Updated: Apr 27, 2026
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Molecular Entanglement and Electrospinnability of Biopolymers
Published on: September 3, 2014
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Shear dependent viscosity of poly(ethylene oxide) in two protic ionic liquids
J A Smith1, G B Webber1, G G Warr2
1Centre for Advanced Particle Processing and Transport, Newcastle Institute for Energy and Resources, The University of Newcastle, NSW 2308, Australia.
Journal of Colloid and Interface Science
|July 7, 2014
Summary
This study investigated poly(ethylene oxide) (PEO) in ionic liquids and water. Solvent nanostructure significantly impacts PEO viscosity and flow behavior, revealing distinct solution regimes.
Area of Science:
- Polymer Science
- Rheology
- Ionic Liquids
Background:
- Polymer solutions exhibit complex rheological behavior dependent on solvent interactions.
- Protic ionic liquids (PILs) offer unique solvent properties compared to traditional solvents like water.
- Understanding polymer behavior in PILs is crucial for developing new materials and applications.
Purpose of the Study:
- To investigate the steady shear viscosity of poly(ethylene oxide) (PEO) in protic ionic liquids (PILs) and water.
- To characterize the concentration regimes and solvent quality for PEO in these media.
- To elucidate the influence of solvent nanostructure on PEO rheology.
Main Methods:
- Steady shear viscosity measurements were performed on 100 kDa PEO.
- Solutions were prepared in ethylammonium nitrate (EAN), propylammonium nitrate (PAN), and water.
- Huggins plots were used to determine solvent quality and transition concentrations.
Main Results:
- Zero shear viscosity increased with polymer concentration, defining dilute, semi-dilute, and network regimes.
- Huggins analysis indicated good (water), good-theta (EAN), and theta (PAN) solvent conditions.
- Differences in transition concentrations and shear thinning behavior were observed between EAN and PAN, linked to solvent nanostructure.
Conclusions:
- Solvent nanostructure in ionic liquids significantly affects polymer solution rheology.
- PEO exhibits distinct concentration-dependent viscosity behavior in PILs and water.
- The findings highlight the importance of solvent properties in polymer science and material design.
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