Architecting Porosity Through Monomer Engineering: Hypercrosslinked Polymers for Highly Selective CO2 Capture from CH4 or N2

Natural gas purification and the mitigation of carbon dioxide (CO₂) emissions from flue gases are critical steps in alleviating the greenhouse effect and significantly mitigate multiple environmental challenges associated with global warming. Hypercrosslinked polymers (HCPs) have become a hot topic as prospective adsorbents for gas purification and separation, owing to their low cost and scalability. Hence, TPB-Ben, TPB-Nap, and TPB-Ant were synthesized through a solvent knitting strategy, with the modification in the size of the monomers serving as a distinctive feature. This alteration aimed to explore the impact of phenyl ring quantity on the polymers' gas adsorption and separation efficiency. All HCPs showed outstanding selective separation capability of CO₂ from CO₂/CH₄ and CO₂/N₂ mixtures, such as TPB-Ben-3-2 (CO₂/CH₄: 10.77; CO₂/N₂: 59.72), TPB-Nap-3-2 (CO₂/CH₄: 9.12; CO₂/N₂: 61.31), and TPB-Ant-3-2 (CO₂/CH₄: 10.00; CO₂/N₂: 62.89), which could be potential candidate adsorbents for natural gas purification and CO₂ capture. Considering the mild reaction conditions, low cost, efficient gas adsorption, and the potential for scalable production, these polymers are considered ideal selective solid adsorbents for capturing CO₂. This further highlights the significance of the solvent knitting strategy.