Antibacterial properties of polyvinylimidazole-modified ultrafiltration membranes

Ultrafiltration (UF) membrane is a core technology for wastewater treatment, but membrane fouling causes a decline in their flux and shortens their service life, making it a key bottleneck issue. In this study, polyvinylimidazole (PVIm) was loaded onto the surface of polyvinylidene fluoride (PVDF) membranes to prepare antibacterial UF membranes by utilizing the adhesion effect of polydopamine (PDA). The inhibitory ability of the modified membrane against Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ) was studied using scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). The experimental results show that 10 % PVIm was the optimal dosing for UF membrane modification (defined as M10 membrane). The M10 membrane exhibited an outstanding antibacterial ability of 79.2 % for E. coli and 68.5 % for S. aureus , respectively. Meanwhile, its surface was smoother and had a higher pure water flux, which could be a good candidate for water and waste water treatment. In summary, PVIm modified UF membranes are simple to prepare with good antibacterial capacities, providing an effective and promising strategy for wide application in urban sewage treatment.