POLYMER
·
2021
·
IF 4.43
Yu Zhang,Won Hee Lee,Jong Geun Seong,Junming Dai,Shichao Feng,Yinhua Wan,Young Moo Lee,Yongbing Zhuang
The physical and gas transport properties of Tröger's Base (TB)-based polyimides (PI-TBs) synthesized by isomeric monomers were rarely reported. Here, a series of PI-TBs was synthesized from two iso -ether dianhydrides [4,4′-oxydiphthalic anhydride (4,4′-ODPA)/3,4′-oxydiphthalic anhydride (3,4′-ODPA)] and two iso -biphenyl dianhydrides [3,3′,4,4′-biphenyltetracarboxylic dianhydride (4,4′-BPDA)/3,4′-biphthalic anhydride (3,4′-BPDA)], with two diamines, 2,5-dimethyl-1,4-phenylenediamine (DPD) or 2,6-diaminotoluene (DAT). The solubility, microporosity, chain packing, mechanical performance and thermal stability, and gas transport properties were investigated for the PI-TBs derived from the isomeric dianhydrides. The polyimides derived from DPD and appropriate dianhydrides had better solubility and film-forming capability, mechanical properties , and higher gas permeability than those from DAT analogues. Furthermore, the polyimides based on different isomeric dianhydrides showed good solubility, mechanical properties, and high thermal stability and glass transition temperatures ( T g s), up to 400 °C. The chemical structures of isomeric dianhydrides have a noticeable influence on the chain packing and gas separation performance of the PI-TBs. The PI-TBs with rigid 3,4’-/4,4′-BPDA residues showed microporosity and their BET values in the range of 235.2–324.9 m 2 /g. The PI-TB membranes from the 3,4′-BPDA showed both higher gas permeability and selectivity (H 2 /CO 2 , H 2 /CH 4 , CO 2 /CH 4 ) compared to those from the 4,4′-BPDA. On the contrary, the PI-TB membranes from the 3,4′-ODPA had lower gas permeability with improved gas selectivity compared to those from the corresponding 4,4′-ODPA.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2018
·
IF 6.578
Shasha Zhao,Jiayou Liao,Danfeng Li,Xiaodong Wang,Nanwen Li
The novel gas separation membranes have been prepared by blending highly gas permeable polymer of intrinsic microporosity (PIM-1) and with Tröger's Base polymer (TB). Interestingly, it was found firstly that the PIM-1 polymer was miscible with Tröger's Base polymer in any proportion. It was assumed that the excellent compatibility between two polymers could be attributed to the interaction between CN group in PIM-1 and N atoms in Tröger's Base moieties, as confirmed by ATR-IR results. Thus, flexible, tough and transparent blending membranes (PIM/TB) at different compositions between PIM-1 and TB were obtained by solution casting. The SEM results further confirmed the homogeneous morphology of blending membranes, indicating the excellent compatibility between two polymers. The gas separation performance testing by the volume-constant method suggested that the PIM/TB blending membrane showed lower pure gas permeability but higher ideal permselectivity than that of the pristine PIM-1 membrane, probably due to the lower d-spacing of TB polymers from commercial aromatic diamine which has a rotatable bond as confirmed by XRD results. The highest ideal permselectivity of CO 2 /CH 4 was obtained for PIM/TB (6:4) membranes with CO 2 permeability of 2585Barrer. Moreover, the excellent anti-plasticization ability of CO 2 was observed for the blending membranes. The temperature dependence of gas separation and ideal permselectivity had also been observed for the membranes. The results suggested that the ideal permselectivity, particularly for the CO 2 /N 2 and CO 2 /CH 4 at lower temperature were much higher than that of the membrane at high temperature in spite of the decreasing permeability of CO 2 . The highest ideal permselectivity was achieved as high as 54.3 for CO 2 /N 2 at − 25 ℃ for PIM/TB(8:2) membrane. Thus, the strategy of blending Tröger's Base with PIM-1 showed a promising approach for high performance gas separation membrane.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
·
IF 8.1
Zhuoyi Huang,Junbo Yue,Shuzheng Sun,Feichao Wu,Jingde Li,Gang Li,Nanwen Li,Yanqin Yang
The typical procedure used to fabricate mixed matrix membranes (MMMs), where the pre-obtained filler and polymer are simply mixed together before casting, often suffers from limited polymer-filler adhesion. Herein, we prepare a series of novel MMMs with improved interfacial compatibility by preparing the matrix (Tröger’s base polymer, TB) and the filler (three-dimensional Tröger’s base-bridged porous network, 3D-TB) under the same reaction system, where in-situ crosslinking reaction between them happens simultaneously. Thanks to the excellent interfacial miscibility, the as-developed 10 wt%_3D-TB@TB membrane shows the tensile strength and elongation stain at break of 65.4 MPa and 10.12 %, respectively, which are higher than those of its counterpart synthesized by conventional procedure (55.82 MPa and 7.05 %, respectively). More importantly, both the gas permeability and selectivity of the in-situ crosslinked MMMs show an obvious improvement involving CO 2 /N 2 , CO 2 /CH 4 , and O 2 /N 2 separation. Specifically, for O 2 /N 2 binary gas separation, the 10 wt%_3D-TB@TB membrane displayed a O 2 permeability of 53.2 Barrers and O 2 /N 2 selectivity of 6.1, which are improved by 72 % and 45 % in comparison to the unfilled membrane, overcoming the 2008 Robson upper bound. Moreover, the physical aging of the in-situ crosslinked MMMs is also effectively controlled. These results demonstrate that the in-situ polymerization and crosslinking is an outstanding approach for the construction of defect-free MMMs with enhanced gas separation performances.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
POLYMER
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2022
·
IF 4.432
Junbo Yue,Jingjing Hou,Yixuan Li,Yanqin Yang,Lu Han,Shuzheng Sun,Jingde Li
Here we report the synthesis of branched Tröger's base polymers ( x -BTB) with different degree of tetraphenylmethane branch structure by incorporating varied amounts of tetrakis(4-aminopheny)methane into the main chains of Tröger's base polymer (TB). We show that branching increases porosity of x -BTB, leading to improved gas permeability . Specifically, the BET surface area and pore volume of x -BTB polymers increase continuously from 410 to 544 m 2 g −1 and 0.584–0.607 cm 3 g −1 , respectively, for branched polymers containing progressively more branch structure. For CO 2 /N 2 , CO 2 /CH 4 , and O 2 /N 2 binary gas separation, a significant improvement in the gas permeability without obvious compromising the membrane selectivity is observed on the x -BTB membranes with higher branch degree. In particular, for CO 2 /N 2 binary gas separation, the CO 2 permeability of 5 wt%-BTB membrane is 145 Barrers, creating an enhancement of 64.8% as compared to TB membrane. Moreover, x -BTB membranes are much more resistant to physical aging than TB membrane. These results suggest that introduction of tetraphenylmethane branch structure is an effective strategy to fabricate polymeric membranes with high performance suitable for gas separation applications.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
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2025
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IF 7.4
Huimin Chen,Xin Li,Wenjiang Li,Aoao Lu,Chenguang Li,Qiang Li,Dabin Liu,Hongfei Ma,Binbin Wang
The safe long-term storage of nitrocellulose (NC) has become increasingly challenging under extreme environmental conditions due to accelerated NO x release, which promotes self-catalytic decomposition of NC. In this study, Tröger’s base (TB) was integrated into porous organic polymers (POPs) to achieve dual functionality: efficient physical adsorption and stable in-situ chemical fixation of NO x within confined pore spaces. Solid-state CP/MAS 13 C NMR spectroscopy and quantum chemical calculations were employed to confirm that NO x immobilization occurs preferentially at the ortho positions of tertiary amine moieties on aromatic rings. Among the synthesized materials, the polymer resulting from the Trögerization of the Tetrakis (4-aminophenyl) methane (TAPM-TB) was identified as the optimal adsorbent, characterized by accessible ortho-active sites, a microporous structure, and an exceptional NO x uptake capacity of 3.31 mmol/g under standard conditions. Furthermore, TAPM-TB was demonstrated to extend the stability time of NC by 3.23 times in methyl violet tests. These findings highlight a novel strategy for designing materials capable of simultaneous physical adsorption and stable chemical immobilization of NO x or other gases.
研究领域:
材料科学
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环境化学
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高分子化学
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物理化学
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化学工程
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高影响因子
Journal of Materials Chemistry A
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2018
·Vol. 6
·期 27
·13302-13311
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IF 9.931
Chuan Hu,Qiugen Zhang,Chenxiao Lin,Zhen Lin,Ling Li,Faizal Soyekwo,Aimei Zhu,Qinglin Liu
Polymers of intrinsic microporosity (PIMs) represent a novel class of membrane materials attracting much attention over the past decade. But challenges still exist in the preparation of anion exchange membranes (AEMs) due to their poor solubility and brittleness. Here we present a new strategy to synthesize soluble PIMs for high performance AEMs. By combining merits of two Tröger's base units, the synthesized copolymer exhibits good solubility as well as excellent mechanical properties. The copolymer has good solubility in dimethylsulfoxide (DMSO) after little quaternization and thus permits crosslinking with a long-flexible multi-cation agent. The resulting membrane has good dimensional stability (20.8% swelling ratio at 60 °C) and excellent alkaline resistance. Subsequently, this membrane exhibits a high hydroxide conductivity of 103.9 mS cm−1 (80 °C) at a low ion exchange capacity (IEC) of 1.67 meq g−1. Moreover, this membrane achieves a peak power density of 158 mW cm−2 in a single fuel cell at a current density of 330 mA cm−2 at 60 °C. The presented approach is beneficial for developing high performance PIM-based AEMs and highlights the tremendous potential of multi-cation cross-linked Tröger's base AEMs for wide application in energy and separation fields.
研究领域:
材料科学
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化学工程
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能源技术
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2025
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IF 9
Cuijing Liu,Mengtian Bai,Lei Li,Jinhui Zhang,Binyou Zhao,Caimei Wu,Zhifei Sun,Xihong He,Linbo Li,Lianshan Li
Efficient ion-selective membranes are critical for numerous industrial applications, yet achieving simultaneous cation and anion separation remains a significant challenge. Tröger's base (TB) materials, featuring angstrom-scale channels, have emerged as a promising platform for precise ion separation. Herein, two trifunctional monomers, 1,3,5-tris(4-aminophenyl) benzene (TPB) and tris(4-aminophenyl) amine (TPA), were selected to fabricate crosslinked TB membranes. By tuning the TPA doping ratio (0, 50, 100 mol%), three distinct membranes (TPA0, TPA50, TPA100) with progressively reduced pore apertures were fabricated, owing to the more compact molecular architecture of TPA relative to TPB. As a result, TPA100 demonstrates a 4.8-fold enhancement in Li + /Mg 2+ selectivity (157 vs 33) compared to TPA0, along with universal mono-/divalent cations differentiation. Simultaneously, the near-electroneutral channels endow TPA100 with exceptional anion sieving capabilities, achieving high selectivity of 260 for OH − /WO 4 2− . This work not only elucidates the structure-property interplay in TB membranes but also establishes a versatile paradigm for advanced membranes capable of simultaneous cation and anion separation.
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高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2021
·
IF 8.742
Lei Wu,Xiuling Chen,Zhiguang Zhang,Shan Xu,Canghai Ma,Nanwen Li
As a new class of membrane materials, Tröger's base (TB) polymers suffer from CO 2 -induced plasticization , which leads to a loss in their gas separation selectivity . To address this challenge, we describe a new approach for enhancing their plasticization resistance by ring-opening a TB polymer to establish hydrogen bonds between polymer chains. The ring-opened membranes, called TB-OR, exhibit H 2 /CO 2 and H 2 /CH 4 selectivities of 5.1 and 186.7, respectively. High-pressure CO 2 feed measurements reveal that the TB-OR membranes possess better plasticization resistance than untreated TB polymers. The increased plasticization resistance is likely due to hydrogen bonds formed between –N-H groups and N atoms in TB-OR polymers, which reduce the polymer chain mobility and CO 2 -induced swelling of polymers. The design principles open a new route for making molecularly-selective membranes with significantly enhanced CO 2 plasticization resistance that are potentially useful for CO 2 separation and hydrogen purification.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2021
·
IF 8.742
Jiulong Yin,Hai Tang,Zhaozan Xu,Nanwen Li
To improve the mechanical strength and separation performance of sulfonated polysulfone (SPSf) ultrafiltration membranes, Tröger's base (TB) polymer was blended into the casting solution. An acid-base crosslinking structure between the sulfonic acid groups of SPSf and tertiary amine groups in TB would contribute to their good compatibility and influence the membrane formation process, morphology and properties. The formation of acid-base pairs was confirmed by the existence of quaternary amine groups in the X-ray photoelectron spectra of SPSf/TB blend membranes. According to the pore structure analysis of ultrafiltration membranes, the blending of TB polymer into SPSf enhanced the surface and total porosities, and reduced the top layer thickness. In addition, the finger-like pores became more regular and vertically interconnected. The SPSf/TB blend membrane showed a higher water contact angle than SPSf membrane due to the addition of hydrophobic TB polymer and formation of acid-base crosslinking structure. The SPSf/TB blend membranes showed higher pure water fluxes (127.4–342.7 L m −2 h −1 ) than the SPSf membrane (51.6 L m −2 h −1 ). All membranes showed similar retention factor for bovine serum albumin (BSA), a model protein foulant. In static experiments, the amount of BSA adsorbed by the SPSf/TB blend membranes was much lower than that of the pristine SPSf membrane because the enhanced charge of the blend membranes (ζ = −72.46 ~ −79.17 mV) strengthened the electrostatic repulsion between membrane surface and BSA. The flux recovery ratio after three ultrafiltration cycles using SPSf/TB blend membranes was lower than that of SPSf membrane because pore blockage and irreversible pollution occurred more easily under a high flux, larger average pore size, and lower hydrophilicity. The introduction of TB polymer enhanced the mechanical strength of the ultrafiltration membrane due to the formation of acid-base crosslinking structure between TB polymer and SPSf.
研究领域:
材料科学
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膜技术
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聚合物化学
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环境工程
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DOI
高影响因子
ChemSusChem
·
2018
·Vol. 11
·期 5
·916-923
·
IF 7.411
Zhenggong Wang,Huiting Ren,Shenxiang Zhang,Feng Zhang,Jian Jin
Graphical Just touching base : New carbon molecular sieve (CMS) membranes are fabricated with the use of a Tröger's base (TB)-based microporous polyimide as the polymer precursor, and their gas-separation performance is investigated. The comprehensive gas-separation performance of the TB–CMS membranes is improved relative to that of most state-of-the-art CMS membranes derived from common polyimides reported so far. Carbon molecular sieve (CMS)-based membranes have attracted great attention because of their outstanding gas-separation performance. The polymer precursor is a key point for the preparation of high-performance CMS membranes. In this work, a microporous polyimide precursor containing a Tröger's base unit was used for the first time to prepare CMS membranes. By optimizing the pyrolysis procedure and the soaking temperature, three TB–CMS membranes were obtained. Gas-permeation tests revealed that the comprehensive gas-separation performance of the TB–CMS membranes was greatly enhanced relative to that of most state-of-the-art CMS membranes derived from polyimides reported so far.
研究领域:
材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Tingting Huang,Jiulong Yin,Hai Tang,Ze Zhang,Di Liu,Shasha Liu,Zhaozan Xu,Nanwen Li
Tröger's base polymer (TB) has been proved to be applicable to prepare ultrafiltration (UF) membrane and the antifouling property could be improved by hydrophilic modification of TB polymer via a two-step ring-opening reaction transforming the tertiary amine into water-affinitive secondary amine. To improve the permeability and antifouling performance of TB-based UF membrane, a zwitterion-modified Tröger's base polymer (ZTB) was synthesized via one-step reaction and simply blended into the TB membrane matrix. The chemical structure of ZTB was characterized by 1 H NMR and X-ray photoelectron spectroscopy (XPS). The TB/ZTB blend polymers and membrane showed higher hydrophilicity than the pristine TB polymer and membrane. The pore structure can be adjusted via ZTB blending content by affecting the cloud point of casting solution and membrane formation process during non-solvent induced phase separation. The total porosity and average surface pore size of UF membrane were increased by blending ZTB. The permeability and retention factor for BSA of UF membrane were simultaneously enhanced. The static BSA adsorption of UF membrane was reduced from 90.6 μg/cm 2 of the pristine TB membrane to 46.8 μg/cm 2 of TB/ZTB-1.0 membrane. The higher flux recovery ratio of TB/ZTB blend membrane than pristine TB membrane after three fouling-cleaning cycles further demonstrated the enhanced antifouling ability of the TB/ZTB blend membrane. Therefore, the zwitterionization of TB polymer is a feasible method for the permeability and antifouling property enhancement of TB-based UF membrane.
研究领域:
材料科学
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环境工程
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Chenglong Yang,Shuqi Liu,Qiyue Zhao,Xinfan Zhang,Zhenggong Wang,Feng Zhang,Jian Jin
Organic solvent nanofiltration (OSN) membranes with precise molecular-sieving performance have become increasingly important in chemical and pharmaceutical industries, desiring superior membranes with both high permeability and selectivity. Herein, the V-shape Tröger's base (TB) structure is incorporated in the polyamide network to engineer microporosity as well as the molecular-sieving performance of the thin-film composite (TFC) polyamide membrane for organic solvent nanofiltration (OSN). The TFC membrane containing the TB structure features a rigid and contorted chain structure, which affords high and stable methanol permeability in OSN applications. Furthermore, the H-bond interaction between the H of amide groups and N in TB reinforces the interchain interaction, endowing the membrane with a precise selectivity to organic solutes. The as-prepared TFC membrane demonstrated high methanol permeance of 16.6 L m −2 h −1 bar −1 and sieving performance to organic molecules with molecular weight cut-off (MWCO) down to 349 Da. Furthermore, the membrane demonstrates shape selectivity for organic solutes, exploiting the fine microporous structure. This study may provide insights into the molecular design of TFC membranes by finely tuning the molecular features for precise solute separations.
研究领域:
材料科学
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化学工程
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分离技术
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DOI
高影响因子
危险品化学品经营许可证（带存储）