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Updated: Jan 30, 2026

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Synthesis of Hydrogels with Antifouling Properties As Membranes for Water Purification
Published on: April 7, 2017
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Highly Asymmetric Water Permeation in Dense Laminated Membranes
Luca Grillo1, Christoph Weder1
1Adolphe Merkle Institute, University of Fribourg, Chemin des Verdiers 4, Fribourg 1700, Switzerland.
Summary
We developed novel laminated membranes with directional water transport. An adhesive layer improved adhesion, achieving high asymmetry for applications in separation and wound care.
Area of Science:
- Materials Science
- Polymer Science
- Chemical Engineering
Background:
- Dense laminated membranes exhibit directional permeation, crucial for separation, wound care, and packaging.
- Theoretical models exist for asymmetric permeation, but experimental studies are limited.
Purpose of the Study:
- To engineer dense asymmetric laminated membranes with enhanced directional water transport.
- To overcome interfacial adhesion issues in hydrophilic/hydrophobic polymer bilayers.
Main Methods:
- Fabrication of membranes using hydrophilic poly(vinyl alcohol) (PVA) and hydrophobic poly(ethylene terephthalate) glycol (PETG).
- Optimization of PVA and PETG layer thicknesses via modeling.
- Incorporation of a poly(styrene-block-ethylene-ran-butylene-block-styrene)-graft-maleic anhydride) (SEBS-MA) adhesive layer to improve interfacial adhesion.
Main Results:
- Successfully overcame delamination issues using the SEBS-MA adhesive layer, which enhances bonding via maleic anhydride (MA) group reactions.
- Achieved high asymmetry factors up to 6.7, among the highest reported values.
- Demonstrated directional water transport driven by moisture-induced plasticization of the PVA layer at high relative humidity (RH).
Conclusions:
- Dense asymmetric laminated membranes with significantly improved interfacial adhesion were successfully fabricated.
- The developed membranes exhibit high directional water transport, promising for advanced separation and biomedical applications.
- The SEBS-MA adhesive layer is key to enabling robust hydrophilic-hydrophobic membrane structures.
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