Stimuli-Responsive Membranes through Sustainable Aqueous Phase Separation.

Area of Science:

• Materials Science
• Chemical Engineering
• Polymer Science

Background:

• Polymeric membranes are vital for water purification and dialysis but rely on hazardous solvents.
• Current fabrication methods are unsustainable, costly, and pose health risks due to toxic solvents.

Purpose of the Study:

• To develop a sustainable, aqueous-based method for fabricating porous polymeric membranes.
• To achieve control over membrane structure and introduce responsive properties for enhanced functionality.

Main Methods:

• Utilized Poly(4-vinylpyridine) (P4VP), a pH-responsive polymer, dissolved at low pH.
• Employed an aqueous phase separation technique by switching to high pH for controlled solidification into porous structures.
• Demonstrated control over membrane morphology, yielding microfiltration and nanofiltration membranes.

Main Results:

• Successfully fabricated porous membrane films using a green aqueous phase separation process.
• Achieved tunable control over membrane structure, producing both symmetric microfiltration and asymmetric nanofiltration membranes.
• Developed pH-responsive membranes with tunable properties based on cross-linking, enabling chemical-free cleaning.

Conclusions:

• The proposed aqueous phase separation method offers a sustainable alternative for membrane fabrication.
• This approach provides precise control over membrane structure and introduces valuable responsive properties.
• The developed membranes are suitable for advanced applications, including efficient and eco-friendly water treatment and dialysis.