Preparation and Properties of Sulfonated Graphene-Modified Ultrafiltration Membranes

The unique benefits of membrane therapy technology make it a popular choice. However, polyvinylidene fluoride (PVDF) and polysulfone (PSF) can readily become contaminated in practical applications. Therefore, in this study, sulfonated graphene oxide (SGO) was doped as an additive at various concentrations, along with dopamine (DA) and silver (Ag) as surface modifiers, to prepare a DA-Ag-modified SGO/PSF/PVDF ultrafiltration membrane with enhanced antipollution performance. The water flux, mechanical strength, and other characterization tools were then applied to analyze the hydrophilicity and structural composition of the membrane. The flux measurement demonstrated that SGO had better hydrophilicity and contamination resistance than graphene oxide (GO). The membrane exhibited the best performance when SGO was added at 0.3 g in the casting solution. The result showed a water flux of 675.80 L m-2 h-1, which was 1.27 times greater than that of the neat membrane. Furthermore, the retention of bovine serum albumin (BSA) was 96.00% and the flux recovery was 85.60%. The antibacterial rate against Escherichia coli and Staphylococcus aureus was up to 97.96% and 96.20%, respectively. Interestingly, the membrane still implied a sustainable antimicrobial effect after 90 days, demonstrating its long-lasting bacteriostatic properties.