Properties and preparation of TiO₂‐HAP@PVDF composite ultrafiltration membranes

Abstract The non‐solvent induced phase separation technology was introduced to formulate titanium dioxide (TiO 2 )‐hydroxyapatite (HAP) composite modified polyvinylidene fluoride (PVDF) ultrafiltration (UF) membranes, and research was conducted to explore the effect on PVDF UF membrane performance exerted by different addition amounts (0–1.0 wt%) of TiO 2 ‐HAP composite. The results indicated that when 0.3% TiO 2 ‐HAP composite was added, the composite membranes had a through‐channel structure, with a uniform pore structure on the surface, so that they possessed a certainly raised pure water flux. Specifically, in contrast to the pure PVDF membrane, 0.3%‐TiO 2 ‐HAP@PVDF UF membrane exhibited an incremented pure water flux by 59.09%. Besides, TiO 2 ‐HAP@PVDF UF membranes had decreased rejection rate of bovine serum albumin (BSA) together with water contact angle to 58.62% and 70.17°, respectively, compared to the pure PVDF membrane (85.52% & 92.75°), showing good hydrophilicity. Several pure water flux tests on the composite UF membranes revealed that the flux tended to be stable after the 4th test. In summary, the addition of TiO 2 ‐HAP composite is capable of efficiently ameliorating PVDF base membranes from the aspects of microstructure, hydrophilicity, antifouling properties, as well as stability, allowing a good application prospect in actual water treatment. Highlights The HAP can solve the poor adsorption of TiO 2 . The TiO 2 can improves the interfacial adhesion between HAP and polymer. The TiO 2 ‐HAP composite with excellent stability, corrosion resistance and et al. The TiO 2 ‐HAP@PVDF UF membrane with anti‐pollution performance and stability.