Husna Asmaul, Hossain Iqubal, Jeong Insu, Kim Tae-Hyun
Organic Material Synthesis Laboratory, Department of Chemistry, Incheon National University, Incheon 22012, Korea.
Research Institute of Basic Sciences, Incheon National University, Incheon 22012, Korea.
Polymers (Basel). 2022 Feb 9;14(4):655. doi: 10.3390/polym14040655.
Mixed matrix membranes (MMMs) have attracted significant attention for overcoming the limitations of traditional polymeric membranes for gas separation through the improvement of both permeability and selectivity. However, the development of defect-free MMMs remains challenging due to the poor compatibility of the metal-organic framework (MOF) with the polymer matrix. Thus, we report a surface-modification strategy for a MOF through grafting of a polymer with intrinsic microporosity onto the surface of UiO-66-NH. This method allows us to engineer the MOF-polymer interface in the MMMs using Pebax as a support. The insertion of a PIM structure onto the surface of UiO-66-NH provides additional molecular transport channels and enhances the CO transport by increasing the compatibility between the polymer and fillers for efficient gas separation. As a result, MMM with 1 wt% loading of PIM-grafted-MOF (PIM-g-MOF) exhibited very promising separation performance, with CO permeability of 247 Barrer and CO/N selectivity of 56.1, which lies on the 2008 Robeson upper bound. Moreover, this MMM has excellent anti-aging properties for up to 240 days and improved mechanical properties (yield stress of 16.08 MPa, Young's modulus of 1.61 GPa, and 596.5% elongation at break).
混合基质膜（MMMs）通过提高透气性和选择性来克服传统聚合物膜在气体分离方面的局限性，因此受到了广泛关注。然而，由于金属有机框架（MOF）与聚合物基质的相容性较差，制备无缺陷的MMMs仍然具有挑战性。因此，我们报道了一种通过将具有固有微孔性的聚合物接枝到UiO-66-NH表面来对MOF进行表面改性的策略。这种方法使我们能够以Pebax为载体，在MMMs中设计MOF-聚合物界面。在UiO-66-NH表面插入PIM结构提供了额外的分子传输通道，并通过提高聚合物与填料之间的相容性来增强CO传输，从而实现高效气体分离。结果，负载1 wt% PIM接枝MOF（PIM-g-MOF）的MMM表现出非常有前景的分离性能，CO渗透率为247 Barrer，CO/N选择性为56.1，符合2008年的Robeson上限。此外，这种MMM具有长达240天的优异抗老化性能和改善的机械性能（屈服应力为16.08 MPa，杨氏模量为1.61 GPa，断裂伸长率为596.5%）。
