Antifouling and antibiofouling pH responsive block copolymer based membranes by selective surface modification

Area of Science:

• Materials Science
• Polymer Chemistry
• Surface Chemistry

Background:

• Developing advanced membranes with antifouling and antibacterial properties is crucial for water treatment.
• pH-responsive polymers offer tunable surface characteristics for dynamic membrane applications.

Purpose of the Study:

• To create novel antifouling and antibacterial membranes via selective surface modification of pH-responsive diblock copolymers.
• To investigate the impact of quaternization and zwitterionization on membrane performance and pH-responsiveness.

Main Methods:

• Preparation of nanoporous membranes using self-assembled supramolecular complexes and nonsolvent induced phase separation.
• Selective surface functionalization of polystyrene-b-poly(4-vinylpyridine) (PS-P4VP) copolymers via crosslinking and zwitterionization.
• Characterization using FTIR, XPS, SEM, QCM, and contact angle measurements.

Main Results:

• Successfully functionalized membranes demonstrated enhanced antifouling and antibacterial efficacy.
• Membrane performance was validated through protein adsorption, bacterial cell attachment/killing assays, and Congo red dye rejection.
• Water flux was evaluated under varying pressures and pH conditions, confirming retained pH-switching behavior.

Conclusions:

• Surface modification of PS-P4VP diblock copolymers yields effective antifouling and antibacterial membranes.
• The developed membranes maintain pH-responsive characteristics while exhibiting superior resistance to biofouling and bacterial adhesion.
• These findings present a promising approach for advanced membrane technology in water purification.