Surface modification of ZIF ‐90 with triptycene for enhanced interfacial interaction in mixed‐matrix membranes for gas separation



Abstract Zeolite imidazole framework (ZIF-90) nanoparticles were chemically modified by grafting triptycene moieties. The modified nanoparticles were introduced into a triptycene-based polyimide as fillers to generate mixed matrix membranes (MMMs) for gas separation. The incorporation of “hook-like” triptycene moieties in both dispersed and continuous phases led to intimate contact between the two phases and thus defect-free interfacial morphology, due to the supramolecular interlocking and π–π stacking interaction between triptycene units presented in both phases. The filler/polymer solution showed shear thickening behavior due to such strong interfacial interaction. The separation performance of the prepared composite membranes was investigated as a function of filler loading and particle surface grafting density. Pure-gas permeation results showed that the gas permeabilities increased expectedly as the filler loading increased, with stable or improved selectivities. The reduced permeability relative to pristine polyimide film is likely due to the pore blockage of ZIF-90 upon grafting triptycene moieties on the particle surface. Reducing the grafting density of triptycene moieties led to improved permeability and selectivity suggesting good tunability of this series of new composite membranes. Overall, modification of nanofiller with hierarchical triptycene moieties offers a fundamentally new avenue for creation of composite membranes with unique properties in gas separations.


Attribute NameValues
  • Quinnan Zhang

  • Shuangjiang Luo

  • Jennifer Weidman

  • Ruilan Guo

Journal or Work Title
  • Journal of Polymer Science

  • February

First Page
  • 2675

Last Page
  • 2687

  • 2642-4150

Publication Date
  • 2020-07

  • Magellan SEM

  • Wiley

Date Created
  • 2020-11-20

  • English

Departments and Units
Record Visibility Public
Content License
  • All rights reserved

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