Polymeric membranes have shown tremendous promise for the separation of CO₂ from flue gas streams. However, few systematic studies have been conducted to better understand the impact that chemical functionalities have on membrane‐based gas separation performance. To address this gap, we herein describe the synthesis and gas separation performance of a series of vinyl‐addition polynorbornenes bearing various CO₂‐philic functional groups. To facilitate direct comparison between functional groups, each material was designed to maintain a common polymer backbone. Though the incorporation of CO₂‐philic moieties within a dense polymeric membrane is frequently hypothesized to enhance CO₂ solubility, and thereby increase CO₂/N₂ selectivity, our results demonstrate that the incorporation of CO₂‐philic groups onto a common polymer backbone do not necessarily result in increased gas separation performance. Experimental and computational results demonstrate that the incorporation of amidoxime groups onto a polynorbornene backbone increase CO₂/N₂ selectivity, whereas commonly employed ethereal side chains only increased permeability.

中文翻译：

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使用通用聚合物主链评估官能团对膜介导的CO2 / N2气体分离的影响

聚合物膜已经显示出从烟气流中分离出CO _2的巨大希望。但是，很少进行系统的研究来更好地了解化学功能对基于膜的气体分离性能的影响。为了解决这个空白，我们在这里描述了一系列带有各种CO _2-亲电官能团的乙烯基加成聚降冰片烯的合成和气体分离性能。为便于在官能团之间进行直接比较，每种材料均设计为维持一个通用的聚合物主链。尽管通常假设在致密的聚合物膜中引入亲CO ₂部分，以增强CO _2的溶解度，从而增加CO _2。/ N ₂选择性，我们的结果表明，将CO _2-亲和基团并入普通聚合物主链并不一定会提高气体分离性能。实验和计算结果表明，mid胺肟基团在聚降冰片烯主链上的引入增加了CO ₂ / N _2的选择性，而常用的醚侧链仅增加了渗透性。