Related Experiment Video
Updated: Jun 6, 2026

Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone
Published on: February 23, 2017
Anisotropic ionic conductivity in block copolymer membranes by magnetic field alignment
Pawel W Majewski1, Manesh Gopinadhan, Woo-Sik Jang
1Department of Chemical and Environmental Engineering, Yale University, New Haven, Connecticut 06511, USA.
Magnetic fields align diblock copolymer structures, creating polymer electrolyte membranes with significantly enhanced lithium ion conductivity. This alignment enables direct ion transport, improving performance over non-aligned materials.
Area of Science:
- Materials Science
- Polymer Chemistry
- Electrochemistry
Background:
- Diblock copolymers self-assemble into ordered structures, forming mechanically robust films.
- These films can be used as membranes for selective transport, such as ion conduction.
- Achieving efficient ion transport requires aligning these self-assembled structures.
Purpose of the Study:
- To investigate the use of magnetic fields for aligning diblock copolymer structures.
- To create polymer electrolyte membranes for selective lithium ion transport.
- To optimize ionic conductivity by controlling self-assembly alignment.
Main Methods:
- Self-assembly of liquid crystalline diblock copolymers.
- Alignment of microdomains using strong magnetic fields (up to 6 T).
- Measurement of ionic conductivity as a function of temperature and magnetic field strength.
Main Results:
- Magnetic fields successfully aligned hexagonally packed cylindrical microdomains over macroscopic areas.
- A significant, order-of-magnitude increase in ionic conductivity was observed in aligned membranes compared to non-aligned ones.
- Ionic conductivity exhibited a non-monotonic temperature dependence, decreasing near the order-disorder transition before rising again.
Conclusions:
- Magnetic field-induced alignment is a scalable method for enhancing polymer electrolyte membrane performance.
- Aligned cylindrical microdomains facilitate direct ion transport, leading to superior conductivity.
- Domain-confined ion transport in cylindrical systems shows distinct anisotropic behavior compared to lamellar systems.
More Related Videos
10:53Anionic Polymerization of an Amphiphilic Copolymer for Preparation of Block Copolymer Micelles Stabilized by π-π Stacking Interactions
Published on: October 10, 2016
09:38Fabrication Procedures and Birefringence Measurements for Designing Magnetically Responsive Lanthanide Ion Chelating Phospholipid Assemblies
Published on: January 3, 2018
Related Concept Videos
Paramagnetism
π Electron Effects on Chemical Shift: Overview
Magnetostatic Boundary Conditions
Potential Due to a Magnetized Object
The vector...
Potentiometry: Membrane Electrodes
Induced Electric Dipoles
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...