Cationic methacrylate-based copolymer ultrafiltration membranes with enhanced antibacterial and antifouling properties

To combat biofouling-induced flux decline in membrane processes, we engineered low-cost, environmentally friendly polyester copolymers functionalized with cationic benzyldimethyl[2-[(2-methyl-1-oxoallyl)oxy]ethyl]ammonium chloride (DMBC) and poly(ethylene glycol) methacrylate (PEGMA) via phase inversion. The cationic DMBC induced electrostatic repulsion, yielding ultrafiltration (UF) membranes with tunable pore structures and robust antifouling performance (85.4 % flux recovery after protein adsorption). Simultaneously, the membranes exhibited potent antibacterial activity (>71.7 % Escherichia coli inactivation) through electrostatic disruption of bacterial membranes. Importantly, the use of eco-friendly polyester matrices ensures environmental compatibility, while the scalable fabrication process achieves ultralow material costs. These multifunctional membranes show potential for other applications beyond wastewater treatment, thanks to their customizable surfaces and reliable performance.