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

Membrane based gas separation is an energy efficient and environmentally friendly technology that is widely applied in areas^1-2 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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4. Tozawa, T.; Jones, J. T.; Swamy, S. I.; Jiang, S.; Adams, D. J.; Shakespeare, S.; Clowes, R.; Bradshaw, D.; Hasell, T.; Chong, S. Y., Porous Organic Cages. Nature materials 2009, 8, 973-978.

5. Jones, J. T.; Hasell, T.; Wu, X.; Bacsa, J.; Jelfs, K. E.; Schmidtmann, M.; Chong, S. Y.; Adams, D. J.; Trewin, A.; Schiffman, F., Modular and Predictable Assembly of Porous Organic Molecular Crystals. Nature 2011, 474, 367-371.

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