(157b) Carbon Molecular Sieve Membranes Based on Polymers of Intrinsic Microporosity

From the membrane technology perspective, carbon molecular sieves (CMS) and polymers of intrinsic microporosity (PIMs) have many similarities. Both are considered amorphous microporous materials that often exhibit favorable molecular sieving properties with promising applications in industrially important molecular separations. Therefore, it is not surprising that recent years saw an attempt to conceptually combine those two classes of materials and use PIMs as pyrolysis precursors for CMS membranes. Those attempts capitalized on exploiting the solution-processability (ease of film formation), high glass transition temperatures (high free volume/microporosity), and structural tunability of PIMs with extraordinary molecular separation properties of CMS.

In this talk, we will focus on our recent research that combines fundamental and practical aspects of transforming PIMs-based CMS membrane materials into industrially relevant membranes with potential applications in energy-intensive gas/vapor separations. In addition to the impact of the PIM precursor and pyrolysis conditions, we will emphasize the profound and somewhat surprising influence of CMS selective layer thickness on the gas separation performance as well as aging characteristics. Finally, we will introduce a new approach to further improve the gas separation properties of PIMs-based CMS membranes by utilizing the vapor phase infiltration technique to fabricate nano-hybrid CMS membranes.