共聚聚酰亚胺热重排改性薄膜的制备及气体分离性能  

Preparation copolymerized polyimide thermal rearrangement modified membrane and its CO_(2)/CH_(4) separation performance

作　　者：邹永兰 贾宏葛[2] 徐蕊 赵士君 周俊康 ZOU Yonglan;JIA Hongge;XU Rui;ZHAO Shijun;ZHOU Junkang(College of Chemistry and Chemical Engineering,Qiqihar University,Qiqihar 161000,China;College of Materials Science and Engineering,Qiqihar University,Qiqihar 161000,China)

机构地区：[1]齐齐哈尔大学化学与化学工程学院,齐齐哈尔161000 [2]齐齐哈尔大学材料科学与工程学院,齐齐哈尔161000

出　　处：《膜科学与技术》2023年第3期87-93,共7页Membrane Science and Technology

基　　金：黑龙江省重点研发计划指导类项目(GZ20210034);黑龙江省领军人才梯队后备带头人资助项目(黑人社函2019(278)号)。

摘　　要：采用二胺2,2-二(3-氨基-4-羟基苯基)六氟丙烷(APAF)经硅烷化后与4,4-二氨基二苯醚分别以7∶3,5∶5,3∶7摩尔比和二酐4,4′-(六氟异丙烯)二酞酸酐进行共聚,通过化学亚胺化后得到溶解性好、相对分子质量高、成膜性好的3组共聚聚酰亚胺膜,经过350℃~400℃热处理后,得到不同的热重排改性膜,采用FTIR光谱等手段进行表征.结果表明,所合成的硅烷化聚酰亚胺随着共聚的APAF含量的增加对CO_(2)/CH_(4)的选择性得到提升;而随着热处理温度的升高,其CO_(2)的渗透系数增加,CO_(2)/CH_(4)的气体选择性提高.噁唑环的转化使得聚合物分子链刚性增强,从而达到改善膜的气体分离性能.400℃热处理下得到的热重排(7∶3)膜相较于前驱体膜,CO_(2)的渗透系数从32.82 Barrer提升到275.62 Barrer,提高了8.4倍,热重排后的膜对CO_(2)/CH_(4)的气体分离性能超过2008年Robeson上限.Diamine 2,2-bis(3-amino-4-hydroxy-phenyl)hexafluoropropane(APAF)was silanized and then copolymerized with 4,4-diaminodiphenyl ether in three molar ratios of 7:3,5:5,3:7 and anhydride 4,4'-(hexafluoroisopropene)diphthalic acid.After chemical imination,high molecular weight copolyimide membranes with good solubility was obtained.After heat treatment at 350-400 ℃,different degrees of thermally rearranged modified membranes were obtained.FTIR spectra proved that copolyimide and thermally rearranged modified membranes were successfully prepared.The results showed that the selectivity of CO_(2)/CH_(4) increased with the increase of APAF content of silanized polyimide.As the temperature of thermal rearrangement increases,the permeability coefficient of COz increases,and the gas selectivity of COz/CH_(4) increases.It can be seen that the transformation of oxazole ring enhances the rigidity of the molecular chain and thus improves the gas separation performance of the membrane.The permeability coefficient of CO_(2) in the 400°C thermal rearrangement(7:3)membrane increased by 8.4 times from 32.82 Barrer to 275.62 Barrer,and the gas separation performance of CO_(2)/CH_(4) in the membrane after thermally rearranged exceeded the upper bound of Robeson in 2008.

关 键 词：硅烷化 共聚 聚酰亚胺 热重排 气体分离膜 

分 类 号：TQ11-2357[化学工程—无机化工]