(600a) Vapor Phase Infiltrated AlOx/PIM-1 “Hybrid Scaffolds” As Solution-Processable Amine Supports for CO2 Adsorption

Energy efficient CO₂ capture requires both a sorbent material with high CO₂ capacity and well-designed contactor with high mass transfer rate, excellent heat management, and low pressure drop. State-of-the-art sorbent materials include amine-loaded zeolites and diamine-appended metal-organic frameworks that possess low processability due to their “hard” nature, as a result, they are processed as powders or pellets with low mass transfer rate and high pressure drop. PIM-1, a microporous polymer that is solution processable, can be easily fabricated into structured sorption contactor such as fibers or monolith. In prior research, PIM-1 is discovered as a “molecular basket” for poly(ethylene imine) (PEI), and PEI impregnated PIM possess nanoscale PEI dispersity and excellent processability. However, due to the plasticizing nature of PEI, PIM-1’s micropore structure will collapse under high PEI loadings (~30wt%) and results in lower CO₂ sorption capacity and amine efficiency. In this work, we will present a post treatment method for the polymer, vapor phase infiltration (VPI), that can increase the pore stability without losing its processability or sacrificing the porosity. PIM is fabricated into fiber sorption contactors and then infiltrated with amorphous aluminum oxyhydroxide (AlO_x) nanostrands via VPI which results in a hybrid porous support structure without pore collapsing under 40wt% PEI loading. With the combination of high processability, comparable CO₂ capacity and excellent amine efficiency, the PEI/AlO_x/PIM-1 composite is a promising alternative to PEI loaded mesoporous oxides.