Mixed matrix membrane for hydrogen separation enhanced by Oxacalix[4]arene-Containing porous organic polymers

The mixed matrix membranes (MMMs) have great potential for industrial H₂ enhancement applications. However, some challenges remain to incorporate the nanoporous architectures with industrial processable polymers. In this work, a macrocyclic cavitand from oxacalix[4]arene was integrated into porous polymers via a facile ring-opening-metathesis polymerization (ROMP), the resulting BIT-POP-20 was added to polysulfone matrix to make novel MMMs with different mass ratios. These membranes improved gas permeation rate for CO₂, H₂ and He, compared with pristine polysulfone, and high H₂/N₂ selectivity of 105 was achieved. This huge improved H₂/N₂ separation performances were due to the nanoporous gas passages through the open supramolecular cavities. This work presents an interesting example in designing MMMs using intrinsic macrocyclic cavity in porous polymer backbone that helps increase their performances in gas separations.