JOURNAL OF MEMBRANE SCIENCE
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2023
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IF 9.5
Song Wang,Yan Wang,Yanchao Zhang,Zhiyan Sui,Junjian Yu,Jialin Zhao,Na Li,Yifang Chang,Di Liu,Zhe Wang
The conformation of N-spirocyclic cations has a high alkaline stability and the construction of microphase-separated structures with poly(biphenyl piperidine) (PBP) is one way to improve the performance of AEM. Here, a variety of N-spirocyclic cations were prepared and formed into polycationic side chains with the PBP main chain via the -(CH 2 ) 4 - spacer group. The ion transport efficiency was greatly enhanced by the synergistic effect of the main chain piperidine cations, and the hydroxide conductivity and peak power density of the MDSU-MPBP membrane reached 132.7 mS cm -1 and 295.2 mW cm -2 at 80 °C, respectively. The BM-DSU cation was degraded to a single cation mainly by the S N 2 reaction after 96 h in a 5 M NaOH/D 2 O solution at 80 °C. The N-spirocyclic mono-cation has extremely high alkali resistance, especially the MDSU cation without significant degradation at 80 °C for 1008 h. The B-MDSU double cation tends to undergo the S N 2 reaction at the C2 and C4 positions. The asymmetrically grafted main-chain piperidine cations exhibit poor chemical stability due to the electron-absorbing effect of the phenyl group. the degradation of the MDSU cations increases the hydrophobicity of the side chains, and the MDSU-MPBP membrane has the best alkali resistance, with a conductivity residual of more than 92.8% after immersion in a 5 M NaOH solution at 80 °C for 480 h.
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
·
2023
·
IF 9.5
Ying Jie Liu,Wei Ting Gao,Ai Mei Zhu,Qiu Gen Zhang,Qing Lin Liu
Anion exchange membranes (AEMs) are the core component of anion exchange membrane fuel cells (AEMFCs), among which poly(aryl piperidinium) (PAP) based AEMs have been studied. Herein, we report some scalable di-piperidinium cationic crosslinkers to enhance the mechanical properties , ionic conductivity and alkaline stability of PAP-based AEMs. The results show that the morphology of AEMs can be affected by adjusting the length of crosslinker. PTP-DPC/C6-50% shows a high OH − conductivity (80 °C, 131.2 mS cm −1 ) due to its microphase separation . It also has excellent elongation at break (20.8%) and tensile strength (36.5 MPa). The peak power density of the PTP-DPC/C6-50% based cell can reach 616.2 mW cm −2 under H 2 –O 2 conditions. The crosslinked network formed by long alkyl spacer chains is helpful to improve the alkaline stability of the AEM. After alkaline stability test, the conductivity of the PTP-DPC/C10-50% membrane maintained at 92.2%.
研究领域:
材料科学
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燃料电池技术
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DOI
高影响因子
MONATSHEFTE FUR CHEMIE
·
2023
·Vol. 155
·期 1
·99-104
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IF 1.8
Dong Wenwen,Gong Tengfei,Liu Chaoyang,Lin Jia,Jia Qiang,Chu Changhu
Apixaban is a highly potent, selective, and efficacious inhibitor of blood coagulation factor Xa. A practical and efficient process has been developed for the preparation of the key intermediate of apixaban. Starting from inexpensive 4-chloronitrobenzene and piperidine, an eight-step procedure for the intermediate has been developed. In this case, sodium chlorite is used twice to oxidize the piperidine cycle to the corresponding lactam under a CO 2 atmosphere, resulting in the construction of two lactams. Furthermore, most of these reactions are highly efficient and practical as they occur under mild conditions. Most of the intermediates can be obtained through simple slurry or recrystallization, and column chromatography purification is not necessary. Graphical abstract
研究领域:
药物化学
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有机合成
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
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IF 8.4
Faizal Soyekwo,Changkun Liu,Xin Mao,Ruixin Nie
Efficient magnesium-lithium separation is key to extracting lithium resources from salt lake brines. However, efficient magnesium-lithium separation is constrained by the high magnesium-to-lithium ratios on the nanofiltration separation performance due to the weakened Donnan effect and inherent permeability-selectivity trade-off behaviour. To address this challenge, a dual methylpiperidinium ionic liquid was designed in this work and incorporated into polyamide networks to manipulate the structural properties of polyamide membrane for improved magnesium/lithium separation. We demonstrate that the piperidinium modification of polyamide networks not only modulated and enhanced the morphology, hydrophilicity , free volume and electropositivity, but also synergized the steric hindrance differentiation inside the membrane nanochannels . These structural advantages enabled the modified membrane to achieve high-separation performance with enhanced water permeance of 37.3 L m −2 h −1 bar −1 and Mg 2+ /Li + selectivity of 30.6 (for Mg/Li mass ratio of 31.2). Molecular dynamics simulations further confirmed that the fast water transport and the difference in the ion separation behaviour are strongly correlated to the enhanced structural properties of membranes. We expect this work to provide insightful guidance for engineering high-performance membranes and make contributions in the application of nanofiltration in lithium mining from high Mg/Li ratio brines.
研究领域:
材料科学
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环境工程
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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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2020
·
IF 7.183
Junbin Liao,Huimin Ruan,Xing Gao,Quan Chen,Jiangnan Shen
The use of electrodialysis (ED) fabricated with proton blocking anion exchange membranes (AEMs) is a promising method to realize waste acid reclamation. To develop AEMs with low proton leakage, in this work, we designed a series of N -methylpiperidine (MPRD)-functionalized poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) cross-linked by weak base 1,3-di-4-piperidylpropane (DiPRD). Our investigations demonstrate the weak base cross-linker could enhance the density of membrane matrix and reduce the hydrophilicity of AEM matrix, which have been verified by thermogravimetric analysis and water absorption with low swelling ratio of 2.43%. Benefit from the unique structure with denser membrane matrix and additional protonated weak base piperidine structure, the acid blocking performance of the optimized crosslinked AEM was enhanced with the H + concentration of 1.98 M in concentrate cell during 24 h-ED process at current density of 20 mA cm −2 (initial H + concentration: 1.0 M), outperforming the AEM without cross-linking structure (1.73 M). Nevertheless, it was found that the small-sized proton diffusion in ion-nanochannels of AEM and the aged membrane matrix in ED process with high sulfuric acid concentration resulted in proton leakage to some degree. As a result, a trade-off between the proton blocking and sulfate ion transport of the cross-linked AEMs is achieved. It is believed that this study can provide a guideline for designing advanced proton blocking AEMs.
研究领域:
化学工程
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材料科学
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DOI
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
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2021
·Vol. 35
·期 4
·e6147
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IF 4.105
Sujuan Ge,Yuming Zhou,Xiaoli Sheng,Chunfeng Mao,Lina Zhao,Jianxing Xu,Lei Qiu
Piperidinium-based ionic liquids (ILs) were synthesized under mild conditions by coordinating N -alkyl- N -methylpiperidinium bromide ([Pip 1,x ]Br) with anhydrous AlCl 3 . The weak basicity of N -methylpiperidine had little impact on downstream problems from proton impurities and catalyst poisoning. The results of Fourier transform infrared (FT-IR), electrospray ionization mass spectrometry (ESI-MS), and nuclear magnetic resonance ( 27 Al NMR) confirmed that the active components in [Pip 1,x ]Br-2AlCl 3 ( χ = 0.67) were [Al 3 Cl 9 Br] − and [Al 2 Cl 6 Br] − . Besides, the reaction performance of [Pip 1,8 ]Br-2AlCl 3 under different conditions was carried out by single-factor experiment and further confirmed by orthogonal experimental method. Among these reaction conditions, the optimal combination was the reaction temperature of 40°C, ILs/O molar ratio of 0.2:1, px/O molar ratio of 12:1, and the reaction time of 30 min. Furthermore, [Pip 1,8 ]Br-2AlCl 3 had excellent stability and can be recycled 14 times. It was the high-efficiency catalytic activity and prominent recyclability that made continuous industrial production possible.
研究领域:
化学工程
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催化科学
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DOI
高影响因子
RENEWABLE ENERGY
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2024
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IF 9
Xianfeng Guan,Di Yu,Yu Luo,Shuyu Zhang,Wanzhen Wu,Xu Feng,Tongtong Gao,Wenyu Bai,Shuang Wang
Amino-type polybenzimidazole is prepared, then ionic liquid with three nitrogen positive sites ([CTDTr]Br 3 ) is polymerized into polymeric ionic liquids (PILs) by in-situ radical polymerization, and AmPBI-CTDTr-P x membranes were prepared by piperidinium (PPd) and [CTDTr]Br 3 combination to cross-linked with AmPBI. Following treatment with KOH and phosphoric acid (PA), the ion pairs (N + - H 2 PO 4 − ) generated in the composite membrane system can enhance proton conductivity and facilitate proton transport. The AmPBI-CTDTr-P x membranes shown exceptional PA retention as a result of the alkaline properties of both [CTDTr]Br 3 and PPd, which can engage in acid-base interactions with phosphoric acid. Specifically, the proton conductivity of AmPBI-CTDTr-P 5 at 180 °C is 129.7 mS cm −1 , which is 2.52 times that of pure membranes. Acid retention of AmPBI-CTDTr-P 5 at 80 °C/40 % RH and 160 °C are 64.4 % and 84 %.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
JOURNAL OF VINYL & ADDITIVE TECHNOLOGY
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2024
·
IF 3.8
Xuemei Zeng,Jianxiang Feng,Yulin He,Siyu Cao,Cheng Zhou,Kangqi Li,Jinjing Tan,Shuyi Chen,Yong Xia,Yuejun Liu,Pu Shi,Jin Zhu
Bio-based antioxidants have garnered attention for their sustainability and environmental benefits. In this study, we designed and synthesized three cardanol-piperidine derivatives (HSs) by utilizing hydrogenated cardanol (HC) and piperidine derivatives to improve the aging inhibition of polypropylene (PP). These bio-based antioxidants were intended as eco-friendly alternatives to conventional synthetic antioxidants. The impact of these HSs on the thermal stability, thermo-oxidative stability, and light stability of PP was thoroughly evaluated. The results unveiled that after 5 h of interaction with 2,2-diphenyl-1-picrylhydrazyl free radical, HSs exhibited a remarkable over 5-fold increase in free radical scavenging efficiency as compared to HC. Moreover, the addition of HSs significantly increased the oxidation induction time and the initial oxidation temperature compared to pristine PP. After photo-oxidative aging and thermo-oxidative aging, the HS-dosed PP demonstrated remarkable retention of elongation at break, reaching more than 72% and 69%. From the comparison with physical mixtures and the density functional theory calculations, an intramolecular synergism mechanism is proposed. The intramolecular synergism between hydrogenated cardanol and piperidine derivatives may be the main reason for the inhibition of PP aging. Highlights A method for constructing simultaneous efficient light, thermal, and oxygen stable polypropylene. The mechanism for achieving simultaneous stabilization of light, heat, and oxygen is the intramolecular synergy of phenol piperidine. The essence of intramolecular synergy of cardanol and piperidine derivatives is its' reduced hydrogen bond dissociation energy and energy gap.
研究领域:
材料科学
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化学工程
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高分子科学
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可持续化学
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DOI
高影响因子
JOURNAL OF POWER SOURCES
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2024
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IF 8.1
Jian Gao,Jialin Zhao,Jingyi Wu,Yijia Lei,Na Li,Junjian Yu,Zhiyan Sui,Yan Wang,Jiayao Yang,Zhe Wang
The poly(aryl piperidinium) backbone has outstanding electrical conductivity and chemical stability, which is ideal for the preparation of anion exchange membranes (AEMs). Hence, in this research we prepared a series of high performance AEMs by introducing electron-rich dibenzothiophene (DBT) monomer into poly(aryl piperidinium) polymer backbone. The larger conjugated surface of the DBT monomer and the presence of heteroatoms facilitated intermolecular interactions between the polymers, which induced the generation of highly efficient ion-transport channels within the membranes, as evidenced by atomic force microscopy (AFM) images. The highest molar addition of DBT monomer, QPDBTTP-25 membrane, showed the highest conductivity (190.90 mS cm −1 at 80 °C) while maintaining robust dimensional stability (swelling ratio was 23.66 % at 80 °C). Owing to the advantages of the poly(aryl piperidinium) polymer backbone, the QPDBTTP-25 membrane also exhibited excellent mechanical properties (tensile strength of 53.03 MPa under fully hydrated condition) and durable chemical stability (conductivity retention remained at 93.2% after being immersed in 2 M NaOH solution at 80 °C for 1500 h). The H 2 /O 2 fuel cell test based on QPDBTTP-25 membrane resulted in a peak power density of 384 mW cm −2 at 80 °C.
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
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2019
·
IF 7.015
Nanjun Chen,Chuanrui Lu,Yunxi Li,Chuan Long,Ziming Li,Hong Zhu
A practical polyelectrolyte system to improve the ion conductivity and lifetime of anion exchange membranes (AEMs) is a critical requirement for alkaline membrane fuel cells (AMFCs). Crosslinking is an effective approach to optimize the performance of AEMs. However, ordinary crosslinkers with a hydrophobic structure always make AEMs mechanically brittle. Herein, in response to the requirement of high-performance AEMs, a series of tunable multi-cation-crosslinked poly(biphenyl piperidinium) (PBP-xQ4) membranes were designed and prepared by embedding flexible cationic crosslinkers. The number of alkyl spacers between the cationic groups in the flexible crosslinkers were optimized to 5 and 6 to achieve optimum performance. These PBP-xQ4 membranes simultaneously have high ion conductivity (155 mS/cm at 80 °C) and good dimensional stability, and these membranes can be folded into many shapes. Besides, the crosslinking also promotes the alkaline stability of these membranes in 2 M NaOH at 80 °C: only a slight degradation is detected by 1 HNMR after alkaline treatment for1800 h. All these impressive results in ion conductivity and durability are attributed to clear nanophase separation in PBP-xQ4 membranes. Moreover, the PBP-xQ4 membrane realizes a maximum power density of 234 mW/cm 2 at 80 °C.
研究领域:
材料科学
·
燃料电池技术
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2020
·
IF 7.183
Xinming Du,Zhe Wang,Hongyu Zhang,Yongjiang Yuan,Hui Wang,Zhenguo Zhang
The diffusion dialysis (DD) process based on AEM is considered for the acid recovery from acid effluents. In this work, the novel self-organized nanostructured cross-linked AEMs based on poly (aryl piperidinium) are synthesized for acid recovery. The cross-linked AEMs are designed by introducing 2-bromoethanol and 1,6-dibromohexane into the hydrophobic poly (biphenyl piperidine)s backbone via Menshutkin reaction, and the self-assembled nanostructure is confirmed by TEM imagines. The acid flux is improved by constructing a micro-phase separation structure and hydrogen bond network. The H-bond networks and cross-linking structure improve the selectivity between the acid and salt system without sacrificing IEC values of AEM. The IEC values of PBP-OH-x AEMs are in the range of 2.18–2.21 mmol/g. The AEMs exhibit high H + dialysis coefficients (U H ), ranging from 0.045 to 0.053 m/h, and have good separation factors (S) in the range of 32–56. The prepared PBP-OH-x AEMs have better DD performance, comparing with the commercial membrane DF-120 (U H = 0.009 m/h, S = 18.5). The novel AEMs based on poly (aryl piperidinium) showed the potential to be used in acid recovery via DD.
研究领域:
材料科学
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环境工程
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DOI
高影响因子
TETRAHEDRON
·
2013
·
IF 2.803
Run-Lin Li,Gong-Qing Liu,Wei Li,Yu-Mei Wang,Lin Li,Lili Duan,Yue-Ming Li
3-Chloropiperidine compounds were obtained via Cu(II)-promoted one-pot intramolecular chloroamination of N -benzyl-4-penten-1-amines and subsequent rearrangement. The reaction conditions leading to this skeleton were studied, and the structure of the product was confirmed by NMR as well as X-ray diffraction experiments.
研究领域:
有机化学
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药物化学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）