Modified zeolitic–midazolate framework 8/poly(ether‐block‐amide) mixed‐matrix membrane for propylene and propane separation

In this study, we fabricated a dual‐layer PES–poly(ether‐block‐amide) (PEBA) composite membrane that included zeolitic–midazolate framework 8 (ZIF‐8) particles and evaluated it for propylene and propane separation under pure and mixed feed conditions. To improve the performance, compatibility, and distribution of particles in the polymer matrix, the ZIF‐8 particles were modified by 3‐(triethoxysilyl) propyl amine (APTES) and 3‐(trimethoxysilyl) propyl amine (APTMS) amino silane coupling agents. Particle modification did not have much effect on the structure and particle size and slightly reduced the membrane specific surface area. The modified particles tended to be in the soft section. At the high loading rate of modified particles, their appropriate compatibility increased the membrane gas permeability () and selectivity. APTES with the proper chain length compared with APTMS had a higher and the same selectivity. The best performance (by 32.1 gpu) was found in PES–PEBA–ZIF‐8–APTES 20%. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46273.