Zwitterionic copolymer self-assembly for fouling resistant, high flux membranes with size-based small molecule selectivity
Zwitterionic copolymer self-assembly for fouling resistant, high flux membranes with size-based small molecule selectivity
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DOI：
10.1016/j.memsci.2015.07.025
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发表时间：
2015-11-01
影响因子：
9.5
通讯作者：
Asatekin, Ayse
中科院分区：
文献类型：
--
作者：
Bengani, Prity;Kou, Yangming;Asatekin, Ayse
在小分子（< 1500 g/mol）之间表现出与溶质电荷无关的基于尺寸的排斥的膜对于许多分离将是有价值的，但是商业膜在该尺寸范围内表现出差的和不可预测的选择性。这是由于高孔径多分散性和带电的膜表面导致受溶质电荷影响的分离。此外，这些膜容易结垢。自组装是一种有前途的技术，用于制造具有抗污染性、高渗透性和选择性沿着的聚合物膜，同时具有容易制造和可扩展性的机会。我们报告的第一个例子，一类新的膜材料，从自组装的含两性离子的两亲性无规共聚物获得其渗透性，基于尺寸的选择性和耐污染性。两性离子基团由于其与水的高亲和力而强烈抵抗生物大分子污染，并且自组装成尺寸为0.6- 2nm的通道型簇。我们发现，这些共聚物自组装成双连续纳米畴。通过将这些共聚物涂覆到多孔载体上形成的薄膜复合膜表现出高达84 L m（-2）h（-1）bar（-1）的渗透率，是具有类似MWCO的商业膜的三倍以上。它们显示出基于尺寸的选择性，截止值约为1 nm。这与通过透射电子显微镜测量的两性离子域的尺寸紧密匹配，表明渗透通过这些自组装的“纳米通道”发生。“这些膜在蛋白质溶液和油乳液的过滤过程中表现出优异的抗污染性，完全抵抗不可逆的污染，并在过滤过程中保持96%以上的渗透率。这些膜在生物分子分离、药物纯化和废水处理中具有潜在的用途。(C)2015 Elsevier B. V.版权所有。
Membranes that exhibit size-based rejection between small molecules ( < 1500 g/mol) independent of solute charge would be valuable for many separations, but commercial membranes show poor and unpredictable selectivity at this size range. This arises from high pore size polydispersity and charged membrane surfaces that lead to separations affected by solute charge. Furthermore, these membranes are susceptible to fouling. Self-assembly is a promising technique for making polymeric membranes with fouling resistance, high permeability and selectivity along with opportunity for easy fabrication and scalability. We report the first examples of a new class of membrane materials that derive their permeability, size-based selectivity and fouling resistance from the self-assembly of zwitterion-containing amphiphilic random copolymers. Zwitterionic groups strongly resist biomacromolecular fouling due to their high affinity with water, and self-assemble into channel-type clusters of 0.6-2 nm in size. We show that these copolymers self-assemble into bicontinuous nanocdomains. Thin film composite membranes formed by coating these copolymers onto porous supports exhibit permeances as high as 84 L m(-2) h(-1) bar(-1), over three times that of a commercial membrane with similar MWCO. They show size-based selectivity, with a cut-off around 1 nm. This closely matches the size of zwitterionic domains measured by transmission electron microscopy, indicating permeation occurs through these self-assembled "nanochannels." These membranes show excellent fouling resistance during filtration of protein solutions and oil emulsions, completely resisting irreversible fouling and retaining over 96% of their permeance during filtration. These membranes have potential uses in biomolecule separations, purification of pharmaceuticals, and wastewater treatment. (C) 2015 Elsevier B.V. All rights reserved.