(610e) Molecular Dynamics Simulation of Mixed Matrix Membrane Formed By Porous Organic Cage and Polymer with Intrinsic Microporosity

Authors: 
Kong, X., National University of Singapore
Jiang, J., National University of Singapore
Membrane based gas separation is an energy efficient and environmentally friendly technology that is widely applied in areas1-2 such as CO2 capture and sequestration, air separation, and natural gas sweetening. However, the trade-off between permeability versus selectivity still hinders the performance of most polymer based membrane3. A promising strategy to tackle this trade-off is mixed matrix membranes (MMMs) in which a solid porous framework is embedded into a polymer host. Recently, porous organic cages (POC)4-5, organic molecules with intrinsic cages, were in situ crystalized in a polymer of intrinsic microporosity (PIM-1) to form MMMs with enhanced permeability and minimal selectivity sacrifice6. In this work, we study the MMMs formed by POC and PIM-1 using all atom molecular dynamics simulation. By analyzing structural properties (such as free void volume, pore size distribution), thermal properties (such as gas adsorption), and dynamical properties (such as gas diffusivity), we tried to elucidate the reason for the enhanced performance of POC/PIM-1 MMMs. We hope that results from these simulations will provide insights into MMM design and optimization.

References

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