富羧酸基团的共轭微孔聚合物：结构单元对孔隙和气体吸附性能的影响(英文)

Carboxyl-Enriched Conjugated Microporous Polymers: Impact of Building Blocks on Porosity and Gas Adsorption

共轭微孔聚合物(CMPs)骨架中的孔和极性基团对聚合物的气体吸附性能起着重要作用。阐明聚合物中极性基团的效果对该领域的进一步发展是必不可少的。为了解决这个根本问题,我们使用最简单的芳香系统-苯作为建筑单体,构筑了两个新颖的富羧酸基团的CMPs(CMP-COOH@1,CMP-COOH@2),并探讨了CMPs中游离羧酸基团的量对其孔隙、吸附焓、气体吸附和选择性的深远影响。CMP-COOH@1和CMP-COOH@2显示的BET比表面积分别为835和765 m^2?g^(-1)。这两种聚合物在二氧化碳存储方面显示了高潜力。在273 K和1.05×10~5 Pa条件下,CMP-COOH@1和CMP-COOH@2的CO_2吸附值分别为2.17和2.63 mmol?g^(-1)。我们的研究结果表明,在相同的条件下增加聚合物中羧基基团的含量可以提高材料对气体的吸附容量和选择性。

Polar groups in the skeletons of conjugated microporous polymers （CMPs） play an important role in determining their porosity and gas sorption performance. Understanding the effect of the polar group on the properties of CMPs is essential for further advances in this field. To address this fundamental issue, we used benzene, the simplest aromatic system, as a monomer for the construction of two novel CMPs with multi-carboxylic acid groups in their skeletons （CMP-COOH@I and CMP-COOH@2）. We then explored the profound effect the amount of free carboxylic acid in each polymer had on their porosity, isosteric heat, gas adsorption, and gas selectivity, CMP-COOH@I and CMP-COOH@2 showed Brunauer-Emmett-Teller （BET） surface areas of 835 and 765 m2.g^-1, respectively, displaying high potential for carbon dioxide storage applications. CMP-COOH@1 and CMP-COOH@2 exhibited CO2 capture capabilities of 2.17 and 2.63 mmol.g^-1 （at 273 K and 1.05·105 Pa）, respectively, which were higher than those of their counterpart polymers, CMP-1 and CMP-2, which showed CO2 capture capabilities of 1.66 and 2.28 mmol.g^-1, respectively. Our results revealed that increasing the number of carboxylic acid groups in polymers could improve their adsorption capacity and selectivity.