聚酰亚胺的分子链规整性好、链间相互作用力强,但是气体透过偏低,为解决该问题,通过引入芴基致孔基元,利用含芴基结构的9,9-双(4-氨基苯基)芴(FDA)、9,9-双(4-氨基-3-氟苯基)芴(FFDA)和2,2-双[4-(4-氨基苯氧基)苯基]丙烷(BAPP)为单体,制备了一系列自具微孔聚酰亚胺膜(PIM-PI)。结果表明:随着致孔基元比例增加,与无致孔基元的纯膜相比,PIM-PI膜的气体分离性能改善显著。例如6FDA-FFDA/BAPP(8∶2)膜表现出优异的分离性能,CO2渗透率为165.46Barrer和CO2/CH4选择系数为31.65,相较于纯膜,分别增加7.45倍和1.66倍。引入芴基致孔基元的微孔聚酰亚胺膜显著地提高了气体渗透率。
Polyimide has good molecular chain regularity and strong inter-chain interaction force,but it has low gas permeability.In order to solve this problem,a series of polyimides of intrinsic microporosity (PIM-PI) membranes were prepared by introducing fluorene-based pore-forming elements and using 9,9-bis(4-aminophenyl)fluorene (FDA),9,9-bis(4-amino-3-fluorophenyl)fluorene (FFDA) and 2,2-bis[4-(4-aminophenoxy)phenyl]propane (BAPP) containing fluorene-based structure as monomers.The experimental results showed that the gas separation performance of PIM-PI membranes improved significantly with increasing the proportion of pore-forming elements compared with the pure membranes without pore-forming elements.For example,the 6FDA-FFDA/BAPP (8∶2) membrane exhibited excellent separation performance with CO2 permeability of 165.46 Barrer and CO2/CH4 selection coefficient of 31.65,which increased by 7.45 and 1.66 times,respectively,compared with the pure membrane.These results indicated that the introduction of fluorene-based pore-forming elements significantly improved the gas permeability of the microporous polyimide membrane.
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基金资助
黑龙江省重点研发计划指导类项目(GZ20210034)
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