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Abstract The development of porous materials is of great interest for the capture of CO2from various emission sources, which is essential to mitigate its detrimental environmental impact. In this direction, porous organic polymers (POPs) have emerged as prime candidates owing to their structural tunability, physiochemical stability and high surface areas. In an effort to transfer an intrinsic property of a cyclotetrabenzoin‐derived macrocycle – its high CO2affinity – into porous networks, herein we report the synthesis of three‐dimensional (3D) macrocycle‐based POPs through the polycondensation of an octaketone macrocycle with phenazine‐2,3,7,8‐tetraamine hydrochloride. This polycondensation was performed under ionothermal conditions, using a eutectic salt mixture in the temperature range of 200 to 300 °C. The resulting polymers, named 3D‐mmPOPs, showed reaction temperature‐dependent surface areas and gas uptake properties. 3D‐mmPOP‐250 synthesized at 250 °C exhibited a surface area of 752 m2 g−1and high microporosity originating from the macrocyclic units, thus resulting in an excellent CO2binding enthalpy of 40.6 kJ mol−1and CO2uptake capacity of 3.51 mmol g−1at 273 K, 1.1 bar.
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This content will become publicly available on January 13, 2026
Porous Organic Polymers Incorporating Shape‐Persistent Cyclobenzoin Macrocycles for Organic Solvent Separation
Abstract The recovery and separation of organic solvents is highly important for the chemical industry and environmental protection. In this context, porous organic polymers (POPs) have significant potential owing to the possibility of integrating shape‐persistent macrocyclic units with high guest selectivity. Here, we report the synthesis of a macrocyclic porous organic polymer (np‐POP) and the corresponding model compound by reacting the cyclotetrabenzil naphthalene octaketone macrocycle with 1,2,4,5‐tetraaminobenzene and 1,2‐diaminobenzene, respectively, under solvothermal conditions. Co‐crystallization of the macrocycle and the model compound with various solvent molecules revealed their size‐selective inclusion within the macrocycle. Building on this finding, thenp‐POP with a hierarchical pore structure and a surface area of 579 m2 g−1showed solvent uptake strongly correlated with their kinetic diameters. Solvents with kinetic diameters below 0.6 nm – such as acetonitrile and dichloromethane – showed high uptake capacities exceeding 7 mmol g−1. Xylene separation tests revealed a high overall uptake (~34 wt %), witho‐xylene displaying a significantly lower uptake (~10 wt % less than other isomers), demonstrating the possibility of size and shape selective separation of organic solvents.
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- Award ID(s):
- 2204236
- PAR ID:
- 10593939
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie
- Volume:
- 137
- Issue:
- 14
- ISSN:
- 0044-8249
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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