College of Chemistry, Key Laboratory of High Performance Plastics, Ministry of Education, Jilin University, Changchun 130012, PR China.
College of Chemistry, Key Laboratory of High Performance Plastics, Ministry of Education, Jilin University, Changchun 130012, PR China; Zhuhai College of Jilin University, Zhuhai 519041, PR China.
J Colloid Interface Sci. 2020 Jul 15;572:48-61. doi: 10.1016/j.jcis.2020.03.072. Epub 2020 Mar 20.
Hybridization has become a powerful toolbox for developing ultrafiltration membranes with superior properties. However, it remains challenging to give full play to the utility of nanofillers because of poor bonding strength between polymers and inorganic nanomaterials. Herein, hydroxyapatite nanotubes (HANTs) were modified via bio-inspired polydopamine (PDA) and polyethylenimine (PEI) co-deposition. Meanwhile, polysulfone with carboxylation degree of 30% (PSF-COOH-30%) was synthesized by nucleophilic substitution reaction and employed as the membrane matrix. The results showed that when 0.3 wt% HANTs@PDA/PEI was incorporated, the pure water flux of the hybrid membrane achieved about 3.2 times that of the unfilled membrane and the rejection rate of bovine serum albumin (BSA) and humic acid (HA) remained 94.5% and 97.8%, respectively. Meanwhile, the flux recovery ratio for BSA and HA solutions (1 g/L) reached 90.8% and 93.7%, respectively. Specifically, the superiority of UF performance benefited from the synergistic effect of both the carboxylated polymer and the nanofiller. On one hand, the incorporation of HANTs@PDA/PEI promoted the formation of more porous membrane structure and improved the hydrophilicity of the membrane. On the other hand, due to the existence of COOH, the electrostatic repulsion between the membranes and contaminants enhanced the fouling resistance for BSA and HA. Conspicuously, the ease and versatility of co-deposition provide new ideas in the construction of nanohybrid and the favorable improvement renders that appropriate combination of polymer and additive is an effective way for developing future ultrafiltration membranes.
杂化已成为开发具有优异性能的超滤膜的强大工具包。然而，由于聚合物和无机纳米材料之间的结合强度差，充分发挥纳米填料的效用仍然具有挑战性。在此，通过生物启发的聚多巴胺（PDA）和聚乙烯亚胺（PEI）共沉积对羟基磷灰石纳米管（HANTs）进行了改性。同时，通过亲核取代反应合成了羧化度为 30%的聚砜（PSF-COOH-30%），并将其用作膜基质。结果表明，当加入 0.3wt%的 HANTs@PDA/PEI 时，杂化膜的纯水通量约为未填充膜的 3.2 倍，牛血清白蛋白（BSA）和腐殖酸（HA）的截留率分别保持在 94.5%和 97.8%。同时，BSA 和 HA 溶液（1g/L）的通量恢复率分别达到 90.8%和 93.7%。具体来说，超滤性能的优势得益于羧化聚合物和纳米填料的协同作用。一方面，HANTs@PDA/PEI 的加入促进了更多孔膜结构的形成，提高了膜的亲水性。另一方面，由于存在 COOH，膜和污染物之间的静电排斥增强了 BSA 和 HA 的抗污染能力。值得注意的是，共沉积的简单性和通用性为构建纳米杂化材料提供了新的思路，良好的改进效果表明聚合物和添加剂的适当组合是开发未来超滤膜的有效途径。
