Dual-phase microporous polymer nanofilms by interfacial polymerization for ultrafast molecular separation.

Area of Science:

• Materials Science
• Polymer Chemistry
• Separation Science

Background:

• Scalable methods for fine-tuning polymer microporosity are crucial for energy-efficient molecular separations.
• Interfacial polymerization offers a promising route for creating advanced polymer membranes.

Purpose of the Study:

• To develop a dual-phase molecular engineering approach for preparing highly microporous polymer nanofilms.
• To investigate the performance of these membranes for molecular separations, particularly hydrocarbon separations.

Main Methods:

• Utilizing interfacial polymerization to integrate Tröger's base diamine (TBD) and spirobifluorene (SBF) motifs.
• Fabricating ultrathin TBD-SBF polyamide membranes (~20 nm).
• Exploring isomeric effects of aqueous phase monomers to manipulate microporosity.

Main Results:

• Achieved unprecedentedly high surface area in TBD-SBF polyamide membranes.
• Demonstrated up to 220 times improved solvent permeance with a moderate molecular weight cutoff (~640 g mol⁻¹).
• Outperformed conventional polymeric membranes and highlighted potential for hydrocarbon separations.

Conclusions:

• The dual-phase molecular engineering approach provides a scalable method for creating high-performance microporous polymer membranes.
• TBD-SBF membranes exhibit superior solvent permeance, indicating their potential for advanced separation applications.
• SBF-based microporous polyamides show promise for efficient hydrocarbon separations through controlled microporosity.