Novel PVC‐Composited GO–La Ultrafiltration Membrane Based on PEG–PPG Amphiphilic Polymer Modification

Abstract The hydrophilicity, pollution resistance, and mechanical properties of a polyvinyl chloride (PVC)‐composited graphene oxide–lanthanum (GO–La) ultrafiltration membrane were effectively improved using a new polyethylene glycol–polypropylene glycol (PEG–PPG) amphiphilic polymer as the pore‐causing agent and GO–La as the modifier. The modified membranes were analyzed and characterized using Fourier transform infrared spectrometry, scanning electron microscopy, atomic force microscopy, X‐ray photoelectron spectrometry, contact angle measurements, and solid surface zeta potentiometry. The contact angle of the PVC‐composited GO–La ultrafiltration membrane (M2) reached 71°, and its water flux and rejection rate were 520.69 L/m 2 ·h and 94.43%, respectively. The tensile strength was 2.46 MPa and the Young's modulus was 42.41 MPa. The relative water flux of M2 was maintained at ∼0.8 after immersion in a strong acid or alkali solution for 28 days, whereas that of the PVC ultrafiltration membrane was 0.7. After three filtration cycles with BSA as a simulated pollutant, the flux recovery rate of PVC‐composited GO–La ultrafiltration membrane was 71%, whereas that of the PVC ultrafiltration membrane was only 42%. Using Pb 2+ , Zn 2+ , and Cu 2+ aqueous solutions as the simulated pollutants, the FRRs of PVC‐composited GO–La ultrafiltration membrane were 56%, 59% and 54%, respectively, with the rejection rate on Pb 2+ , Zn 2+ , and Cu 2+ reaching ∼95%. After PVC‐composited GO–La ultrafiltration membrane was cleaned by the heavy metal ion catcher, its FRR rose to 67%, 64%, and 65%, respectively. The PVC‐composited GO–La ultrafiltration membrane shows great promise as a high‐performance ultrafiltration membrane for treating wastewater containing heavy metals.