Post‐synthesis amination of polymer of intrinsic microporosity membranes for CO₂ separation

Abstract

Membrane separation is an energy-saving technology for carbon capture. However, it is subjected to permeability-selectivity trade-off limitation. Although chemical functionalization is proposed to boost separation efficiency, controlling sorptiondiffusion process remains extremely challenging. In this study, a facile, controllable, and versatile chemical vapor amination strategy is reported to simultaneously tune gas sorption and diffusion in polymer of intrinsic microporosity (PIM)-based membranes for improving carbon capture performance. Through simple exposure in amine vapors under mild conditions, nucleophilic substitution of amines toward ether and halogen groups induce grafting, ring-opening, terminal replacement, chain-scission, and crosslinking of PIM-1, thereby underpinning CO 2 -philicity and tailoring passageway. The prepared CO 2 -philic membranes exhibit substantially improved CO 2 /N 2 selectivity over 30.8, about 226% as that of original one, accompanied by high CO 2 permeability of 2590 Barrer, which can surpass the trade-off upper bound of polymer membranes. Our results reveal that post-synthesis amination is an effective route to obtain high-performance membranes.

Cross-Linked Fluorinated Polyurethanes against Chemical Warfare Agent Simulants: Properties Affected by the Structure of Diisocyanate

“…The free volume is obtained from nanoscale pores randomly distributed in the glassy polymer, and it has an important impact on the permeability resistance of the polymer . Factors such as polymer rigidity, hydrogen bonding and chain segment motion, and intra- and intermolecular cross-linking can affect the free volume distribution of polymers. Here, PALS is used to evaluate the size of the free volume pores of the PU coatings.…”

Advancements in Gas Separation for Energy Applications: Exploring the Potential of Polymer Membranes with Intrinsic Microporosity (PIM)

“…Nevertheless, many of these modifications often lead to decreased surface area or available cavities within the material [62]. Some of the techniques employed include carboxylate-functionalized PIM-1 (cPIM) [63][64][65][66], amidoximefunctionalized PIM-1 [62,67], heterocyclic tetrazole-functionalized PIM-1 [68], thioamidefunctionalized PIM-1 [69] and amine-functionalized PIM-1 [70][71][72][73]. Carboxylate-Functionalized PIM-1 (cPIM-1)…”

“…Recently, Chen et al introduced a facile, controllable, and versatile chemical vapor amination strategy, which simultaneously modifies gas sorption and diffusion properties in PIM-based membranes, resulting in enhanced carbon capture performance [73]. The method involved exposing the membranes to amine vapors under mild conditions, leading to nucleophilic substitution reactions between amines and ether/halogen groups.…”