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Updated: Jul 15, 2026
08:06
Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone
Published on: February 23, 2017
Diastereomeric Monomers Enable Anion-Exchange Membranes With Controlled Local Polymer Backbone Flexibility and High
Si Chen1, Xuchen Lyu1, Triet Nguyen Dai Luong1
1Department of Chemistry, Lund University, Lund, Sweden.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|July 14, 2026
Summary
This study introduces a novel polymer design for anion-exchange membranes (AEMs) that precisely controls water uptake and enhances hydroxide conductivity. Stereochemistry fine-tunes membrane properties for improved performance in electrolysis.
Area of Science:
- Polymer Chemistry
- Materials Science
- Electrochemistry
Background:
- Ion-exchange membrane performance relies on multiple interdependent properties.
- Controlling hydration and ion conductivity is crucial for efficient anion-exchange membranes (AEMs).
Purpose of the Study:
- To design a polymer backbone enabling constrained local flexibility for AEMs.
- To investigate how subtle stereochemical variations influence membrane properties and device performance.
- To establish a stereochemistry-based synthetic strategy for rational AEM design.
Main Methods:
- Synthesized two series of poly(arylene piperidinium) AEMs differing only in stereochemistry.
- Utilized diastereomeric arene monomers with vicinal methyl substitutions.
- Systematically investigated structure-property relationships, hydration behavior, ion transport, and device performance.
Main Results:
- Developed AEMs with constrained local flexibility, suppressing excessive hydration while maintaining high hydroxide conductivity.
- Syn-enriched membranes showed higher water uptake and conductivity, enhancing electrolysis performance.
- Anti-enriched membranes demonstrated improved mechanical robustness and hydration efficiency for ion transport.
Conclusions:
- A stereochemistry-based synthetic strategy allows precise control over AEM properties through minimal structural variation.
- This molecular platform facilitates rational design of high-performance AEMs.
- Controlled hydration and ion transport are achievable via polymer backbone stereochemistry.
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