Improving gas permeation performance of PDMS by incorporating hollow polyimide nanoparticles with microporous shells and preparing defect-free composite membranes for gas separation
Improving gas permeation performance of PDMS by incorporating hollow polyimide nanoparticles with microporous shells and preparing defect-free composite membranes for gas separation
复制标题
将空心聚酰亚胺纳米颗粒与微孔壳结合提高PDMS的气体渗透性能并制备无缺陷气体分离复合膜
DOI：
10.1016/j.memsci.2021.119508
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发表时间：
2021-06-12
影响因子：
9.5
通讯作者：
Xin, Qingping
中科院分区：
文献类型：
--
作者：
Cao, Qianqian;Ding, Xiaoli;Xin, Qingping
近年来，各种类型的中空材料被添加到聚合物基体中以改善聚合物材料的气体渗透和分离性能。在微乳液体系中，以4，4-（9-亚芴基）-二苯胺和1，2，4，5-苯四羰基四氯化物为原料，通过界面聚合制备了具有微孔壳层的中空聚酰亚胺（PI）纳米粒子。制备了自支撑聚二甲基硅氧烷（PDMS）/中空PI纳米粒子混合基质膜，并考察了其气体渗透分离性能。纳米粒子的中空和多孔结构在膜中得到很好的保留，这降低了传质阻力。随着纳米粒子负载量的增加，渗透性先增加后降低，而不牺牲选择渗透性。与O-2和CO2渗透率分别为786和3484 Barrer的纯PMDS膜相比，具有3wt%中空PI纳米颗粒的混合基质膜实现了高达1664 Barrer的O-2渗透性，伴随着2.3的O-2/N-2渗透选择性，以及高达6639 Barrer的CO2渗透性，伴随着2.3的CO2/N-2渗透选择性。2在35 ℃和0.2MPa下的选择渗透性为9.1。通过将多孔聚醚酰亚胺基底浸涂到具有3wt%纳米颗粒的PDMS溶液中来制造混合基质复合膜。所得到的无缺陷的混合基质复合膜表现出优异的O-2和CO2渗透高达1677和6502 GPU，分别。空气分离实验表明，该复合膜可产生富氧渗透流，其浓度可达约100%。30体积%。
Recently, various types of hollow materials have been added into polymer matrices to improve the gas permeation and separation performance of polymer materials. In this study, hollow polyimide (PI) nanoparticles with microporous shells were synthesized by interfacial polymerization between 4,4-(9-fluorenylidene)-dianiline and 1,2,4,5-benzenetetracarbonyl tetrachloride in the microemulsion. Free-standing polydimethylsiloxane (PDMS)/hollow PI nanoparticles mixed matrix membranes were prepared and the gas permeation-separation performance was investigated. The hollow and porous structure of the nanoparticles was well-preserved in membranes, which reduced the mass transport resistance. The permeability firstly increased and then decreased as the nanoparticle loading increased without sacrificing the permselectivity. Compared to the neat PMDS membranes with O-2 and CO2 permeability of 786 and 3484 Barrer, respectively, the mixed matrix membranes with 3 wt% hollow PI nanoparticles achieved a O-2 permeability up to 1664 Barrer accompanied with an O-2/N-2 permselectivity of 2.3 and a CO2 permeability up to 6639 Barrer accompanied with a CO2/N-2 permselectivity of 9.1 at 35 degrees C and 0.2 MPa. Mixed-matrix composite membranes were fabricated by dip-coating the porous polyetherimide substrate into a PDMS solution with 3 wt% nanoparticles. The resultant defect-free mixed-matrix composite membrane showed excellent O-2 and CO2 permeances of up to 1677 and 6502 GPU, respectively. The air separation measurement showed that the composite membranes could produce oxygen-enriched permeate stream enriched to ca. 30 vol%.