Abstract The gas separation of polymers of intrinsic microporosity (PIMs) was enhanced by incorporating bipyrimidine (bpy) into the polymer (PIM-bpy-x) through the polycondensation of a novel tetraphenyl-bipyrimidine monomer. The structures of PIM-bpy-x were investigated with 1H NMR and FT-IR. Because of the excellent heat resistance imparted by the tetraphenyl-bipyrimidine unit, PIM-bpy-x displayed better thermal stability than did PIM-1. These polymers displayed large Brunauer-Emmett-Teller (BET) surface areas, ranging from 656 to 728 m2 g−1. The BET surface area of PIM-bpy-5 was 728 m2 g−1, which was similar to that of PIM-1 (774 m2 g−1). PIM-bpy-x exhibited excellent gas separation performance. PIM-bpy-5 showed the highest CO2 permeability (5141 barrer), which was much higher than that of PIM-1 (4234 barrer). The increase in CO2 permeability is due to the affinity between the N-rich bipyrimidine units and CO2. Furthermore, PIM-bpy-x also showed greater resistance to aging than did PIM-1. All of the above indicate that introducing bipyrimidine units into the polymers can enhance the gas separation performance of PIMs.

中文翻译：

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用于增强气体分离的含有四苯基-联嘧啶的具有固有微孔的新型共聚物

摘要 通过新型四苯基-联嘧啶单体的缩聚，将联嘧啶 (bpy) 加入聚合物 (PIM-bpy-x) 中，增强了固有微孔 (PIM) 聚合物的气体分离。用1H NMR和FT-IR研究了PIM-bpy-x的结构。由于四苯基-联嘧啶单元赋予的优异耐热性，PIM-bpy-x 显示出比 PIM-1 更好的热稳定性。这些聚合物显示出较大的 Brunauer-Emmett-Teller (BET) 表面积，范围为 656 至 728 m2 g-1。PIM-bpy-5 的 BET 表面积为 728 m2 g-1，与 PIM-1（774 m2 g-1）相似。PIM-bpy-x 表现出优异的气体分离性能。PIM-bpy-5 的 CO2 渗透率最高（5141 barrer），远高于 PIM-1（4234 barrer）。CO2 渗透性的增加是由于富含 N 的双嘧啶单元和 CO2 之间的亲和力。此外，PIM-bpy-x 还表现出比 PIM-1 更强的抗老化能力。以上都表明在聚合物中引入联嘧啶单元可以提高 PIMs 的气体分离性能。