Polysulfone ultrafiltration membranes were prepared with sulfobetaine polyimide (s‐PI) via phase inversion process, during which s‐PI migrated and enriched on the surfaces of membranes/pores due to its hydrophilic nature. Therefore, s‐PI not only enhanced surface hydrophilicity, but also acted as a pore‐forming agent. It was proved that the introduction of s‐PI effectively promoted membrane porosity and antifouling ability. Under optimized conditions, the pure water flux of blend membranes reached 220.58 L m⁻² h⁻¹ with a protein rejection ratio of 99.3%, and a flux recovery ratio of 90.86%, indicating the superior antifouling property and filtration performances of zwitterionic polymer blend membranes. Moreover, the blend membrane can stand a temperature of 90°C without degrading its separation performance. Besides excellent thermal stability, the blend membranes exhibited a distinctly advanced mechanical strength due to the addition of rigid s‐PI polymer. Overall, this study provided a facile and scalable method for the preparation of antifouling and thermally stable ultrafiltration membranes.

中文翻译：

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以磺基甜菜碱聚酰亚胺为致孔剂的新型防污热稳定聚砜超滤膜

通过磺基甜菜碱聚酰亚胺（s-PI）的相转化工艺制备了聚砜超滤膜，在此过程中，由于亲水性，s-PI在膜/孔表面迁移并富集。因此，s-PI不仅增强了表面亲水性，而且还充当了成孔剂。事实证明，引入s-PI可以有效提高膜的孔隙率和防污能力。在优化条件下，共混膜的纯水通量达到220.58 L m ^-2 h ^-1蛋白质截留率为99.3％，通量回收率为90.86％，表明两性离子聚合物共混膜具有优异的防污性能和过滤性能。此外，共混膜可以承受90℃的温度而不会降低其分离性能。除了出色的热稳定性外，由于添加了刚性s-PI聚合物，共混膜还表现出明显先进的机械强度。总的来说，这项研究为制备防污和热稳定的超滤膜提供了一种简便而可扩展的方法。