Related Experiment Video
Updated: Aug 6, 2026
08:12
Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
Published on: December 16, 2022
Breaking the Permeability-Selectivity Trade-Off With Irreversible-Knot Rubbery Organic Frameworks
Jiayu Dong1,2, Huan Liu1,2, Liang Huang3
1Key Laboratory of Material Chemistry for Energy Conversion and Storage, Huazhong University of Science and Technology, Ministry of Education, Wuhan, P. R. China.
Advanced Materials (Deerfield Beach, Fla.)
|August 5, 2026
Summary
Researchers developed a new membrane using irreversible chemistry to overcome the permeability-selectivity trade-off in polymer materials. This innovation offers high flux and stable separation for industrial applications.
Area of Science:
- Polymer Science and Engineering
- Materials Chemistry
- Separation Science
Background:
- Polymeric membranes face a fundamental permeability-selectivity trade-off due to chain flexibility versus molecular sieving.
- Rubbery organic frameworks (ROFs) offer potential but suffer from structural instability due to reversible covalent chemistry.
Purpose of the Study:
- To introduce an irreversible chemistry approach for designing polymer networks that overcome the permeability-selectivity limitations.
- To enhance membrane performance and stability for separation applications.
Main Methods:
- Programming "irreversible knots" using β-ketoenamine chemistry into polydimethylsiloxane (PDMS) networks via enol-keto tautomerization.
- Co-programming crosslinking density and chain rigidity to stabilize and optimize membrane microstructure.
- Testing membrane performance in ethanol/water separation and diverse organic/water and gas-pair systems.
Main Results:
- Achieved a record-high flux of 5.4 kg m-2 h-1 for ethanol/water separation, three times higher than conventional PDMS.
- Maintained a high separation factor of 9.2, demonstrating a breakthrough in the permeability-selectivity trade-off.
- Demonstrated top-tier performance across various separation systems and exhibited scalable fabrication, anti-swelling stability, and durability.
Conclusions:
- Established irreversible chemistry as a general paradigm for polymer network design, overcoming traditional limitations.
- The developed "rigidity-programming" strategy offers a versatile platform for advanced functional materials.
- The membranes show significant practical potential for industrial deployment in separation technologies.
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