Building interfacial compatible PIM-1-based mixed-matrix membranes with ?-ketoenamine-linked COF fillers for effective CO2/N2 separation

Mixed matrix membranes (MMMs) with easy scale-up architectures have shown great potential to achieve su-perior CO2 permeance, while their performances are often restricted by the poor interfacial compatibility be-tween fillers and the matrix, and also by blocking of the original channel for gas transmission. Here, a rational design and facile construction of highly permeable MMMs is presented by dispersing triphenyltriazine-based beta-ketoenamine-linked covalent organic framework (TpTta-COF) within solution-processable polymer of intrinsic microporosity (PIM-1). An intimate mixing was achieved by improved compatibility of the components induced by the hydrogen bond interaction between-N-H in TpTta-COF and C---N of PIM-1. The good adhesion avoids the formation of interface defects, preserving the original gas transmission channel. TpTta-COF particles with strong CO2 affinity are evenly distributed in the matrix, forming a fast and continuous channel for CO2 transmission. The physical properties of MMMs were easily tuned, and the as-prepared PIM-1/TpTta-COF-6wt% demonstrates extraordinary stability, high CO2 permeability and CO2/N2 selectivity, surpassing the beta-ketoen-amine-free MMM counterparts. This study provides a feasibly pathway for the development of efficient and high