Mixed matrix membranes (MMMs) are an attractive platform for challenging gas separations since they are the state-of-the-art scalable molecular sieve membranes. Here, the commercially attractive polysulfone (PSF) was grafted by poly(polyethylene glycol) methyl ether methacrylate (PEG) side chains to improve the interfacial interaction with zeolitic imidazolate framework-8 (ZIF-8) nanoparticles and the affinity towards C₃H₆ for enhanced C₃H₆/C₃H₈ separation performance. The PSFPEG graft copolymers monotonically increased the intersegmental distance of polymer chains with increasing the PEG contents based on the XRD results and the density functional theory calculations. Also, the cross-sectional SEM images of MMMs visualized that the interfacial adhesion between ZIF-8 and polymer was improved as the PEG content increased. Both DSC and FT-IR analyses revealed that such an enhanced interfacial adhesion was attributed to a combination of flexible nature of PEG side chains and various chemical interactions. More importantly, the PSFPEG73/ZIF-8 (65/35 vol/vol) MMM enhanced both C₃H₆ permeability and C₃H₆/C₃H₈ permselectivity compared to the PSF/ZIF-8 counterpart by 57% and 55%, respectively. Besides, the equimolar C₃H₆/C₃H₈ mixed gas permeation isotherm exhibited that the PSFPEG73/ZIF-8 (65/35 vol/vol) MMM enhanced the plasticization resistance against C₃H₆ compared to the PSF/ZIF-8 counterpart (e.g., C₃H₆-induced plasticization pressure of 5 vs. 3 atm), demonstrating the significance of the interfacial interaction.

混合基质膜（MMM）是最富挑战性的气体分离平台，因为它们是最新的可扩展分子筛膜。在这里，商业上有吸引力的聚砜（PSF）接枝了聚（聚乙二醇）甲基醚甲基丙烯酸甲酯（PEG）侧链，以改善与沸石咪唑酸酯骨架8（ZIF-8）纳米粒子的界面相互作用以及对C ₃ H ₆的亲和力用于增强的C ₃ H ₆ / C ₃ H ₈分离性能。基于XRD结果和密度泛函理论计算，随着PEG含量的增加，PSFPEG接枝共聚物单调增加了聚合物链的节间距离。同样，MMM的横截面SEM图像显示，随着PEG含量的增加，ZIF-8与聚合物之间的界面粘合性得到改善。DSC和FT-IR分析均表明，这种增强的界面粘合性归因于PEG侧链的柔韧性和各种化学相互作用的结合。更重要的是，PSFPEG73 / ZIF-8（65/35 vol / vol）MMM增强了C ₃ H ₆渗透性和C ₃ H ₆ / C ₃ H ₈与PSF / ZIF-8相比，渗透选择性分别降低了57％和55％。此外，等摩尔C ₃ H ₆ / C ₃ H ₈混合气体渗透等温线显示，与PSF / ZIF-相比，PSFPEG73 / ZIF-8（65/35 vol / vol）MMM增强了对C ₃ H _6的抗塑化性8个对应物（例如，C ₃ H ₆引起的5 at。3 atm的增塑压力）证明了界面相互作用的重要性。