REACTIVE & FUNCTIONAL POLYMERS
·
2024
·
IF 4.5
Yuan Jin,Dan Zhao,Jiaqi Wang,Yifan Li,Meisheng Li,Xiuyang Zou,Shouyong Zhou,Yijiang Zhao,Qi Zhang,Dawei Yang
Poor alkali resistance and low ionic conductivity are the crux of the matter that hinder the commercialization applications of anion exchange membranes (AEMs). Here, we designed and synthesized a range of poly(phenylene oxide) (PPO)-based AEMs with benzyl free side-chain type. After that, the influences of different cationic functional groups, such as quaternary ammonium, imidazole and piperidine, on the membrane performances were examined systemically. The introduction of ether bond-containing side chains to build micro-phase separation structures enhanced the conductivity of AEMs (64 mS·cm −1 at 80 °C). At the same time, the side-chain without benzyl structures effectively avoids the influence of electron withdrawing groups on PPO main chains. Moreover, the steric hindrance effect of the benzene ring can further alleviate the attack of OH − , thereby improving the alkali resistance of the membrane. Molecular dynamics simulations revealed that a well-developed hydrogen bonding network was formed between ether linkages and water molecules in the side-chain structures, which enhanced the electrical conductivity of the membrane. Meanwhile, the prepared membranes owned a good water uptake and a certain dimensional stability. These results provide a basis for the subsequent enhancement of membrane performances.
研究领域:
材料科学
·
燃料电池技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·Vol. 141
·期 42
·e56112
·
IF 2.7
Xunwang Tang,Zongxue Yu,Junlei Tang,Jiaqiang Huang,Xiuzhu Zhang,Jiajia Hou,Guangcheng Yang
The durability of anion exchange membranes (AEMs) and the balance between ionic conductivity and dimensional stability have been the focus of research. To this end, we propose a new type of AEMs with vinyl imidazole as the in situ cross-linking monomer. The rigid-flexible balance within the membrane was adjusted by changing the arrangement of the internal segments of the polymer and introducing different monomers into the main chain. The results showed that the performance of AEMs could be effectively improved by adopting an ether-free backbone and a cationic cross-linking strategy. The swelling rate of all AEMs was less than 20%. The ionic conductivity of BDCP-80 reached 102.74 mS cm −1 at 80°C. Alkaline stability tests showed that the ionic conductivity of all AEMs remained above 82% after 720 h immersion in 2 M NaOH solution at 80°C. This study demonstrated that the simple in situ cross-linking method can effectively improve the overall performance of AEMs and provide an effective way to develop high-performance AEMs.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Fanghui Wang,Zhaonan Sun,Hanfei Zhang,Hong Zhu
A series of SEBS-C6-PIP-yPTP (y = 0–15%) AEMs with good mechanical and chemical stability were prepared by combining the strong rigidity of p-triphenyl, good toughness of SEBS, and excellent stability of PIP cations. After the introduction of a p-triphenyl polymer into the main chain, a clear hydrophilic–hydrophobic phase separation structure was constructed within the membrane, forming a continuous and interconnected ion transport channel to improve ion transport efficiency. Moreover, the molecular chains of the cross-linked AEMs change from chain-like to network-like, and the tighter binding between each molecule increases the tensile strength. The special structure of the six-membered ring makes PIP have a significant constraint effect; when nucleophilic substitution and Hoffman elimination occur at the α and β positions, the required transition state potential energy increases, making the reaction difficult to occur and improving the alkaline stability of the polymer membrane. The SEBS-C6-PIP-15%PTP membrane has the best mechanical properties (Ts = 38.79 MPa, Eb = 183.09% at 80 °C, 100% RH), the highest ion conductivity (102.02 mS. cm–1 at 80 °C), and the best alkaline stability (6.23% degradation at 80 °C in a 2 M NaOH solution for 1400 h). It can be seen that organic–organic covalent cross-linking is an effective means to improve the comprehensive performance of AEMs.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Maolian Guo,Tao Ban,Yajie Wang,Yannan Wang,Yiyang Zhang,Jingsong Zhang,Xiuling Zhu
A series of ether-free polybenzimidazoles (PBIs) containing alicyclic and aliphatic segments were synthesized for the application of anion exchange membranes (AEMs). The PBI-based AEMs prepared in this work (denoted as Pip-PBIs) possessed both high anionic conductivity and alkaline stability by grafting long alkyl chain 1-methylpiperidinium. Benefiting from the random arrangement of aromatic-alicyclic/aliphatic in backbone and their flexible spatial configurations, most Pip-PBIs showed significantly improved solubility in low boiling point solvents namely methanol and isopropanol, which could allow it as ionomer to improve the phase interface between catalyst and AEMs. Meanwhile, the flexible segments in backbone contributed to the formation of ion conductive channel, the Pip-PBI-C achieved the highest hydroxide ions conductivity of 108.8 mS cm −1 at 80 °C, and the conductivity could retain 82.9% after soaking in a 2 M aqueous NaOH at 80 °C for 1536 h. Furthermore, Pip-PBIs demonstrated well oxidation stability in Fenton's reagent (4 ppm FeSO 4 and 3% H 2 O 2 ). Moreover, the H 2 –O 2 fuel cell using Pip-PBI-C as membrane achieved a high open circuit voltage of 1.0 V and a peak power density of 785.6 mW cm −2 at the current density of 1802.9 mA cm −2 .
研究领域:
材料科学
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化学工程
·
能源技术
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2015
·
IF 5.056
Congrong Yang,Suli Wang,Wenjia Ma,Luhua Jiang,Gongquan Sun
The alkaline stability of 1,2-dimethylimidazolium with various N3-substituents (including butyl, benzyl and vinylbenzyl) and corresponding quaternary ammonium small molecular compounds, and the 1,2-dimethylimidazolium- and quaternary ammonium-based membranes are systemically studied in the same condition. The spectroscopy (such as NMR, FT-IR, XPS and mass spectrum) results of the two kinds of small molecular compounds indicate that the quaternary ammonium cations are more stable than 1,2-dimethylimidazolium cations in 3 M KOH at elevated temperature, especially at 80 °C. Moreover, the alkaline stability of the 1,2-dimethylimidazolium cations would be influenced by the N3-substitutions of the imidazolium, and N3-butyl substituted cation shows a better alkaline stability. The quaternary ammonium-based membrane are also more stable than the 1,2-dimethylimidazolium-based membrane in 1 M KOH at 60 °C. In addition, the performance of the alkaline direct methanol fuel cell using quaternary ammonium-based membrane (22 mW cm −2 ) is much better than that of the fuel cell using 1,2-dimethylimidazolium-based membrane (0.04 mW cm −2 ).
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 62
·36374-36385
·
IF 3.049
Chao Wang,Nengxiu Pan,Yuliang Jiang,Junbin Liao,Arcadio Sotto,Huimin Ruan,Congjie Gao,Jiangnan Shen
Novel anion exchange membranes with enhanced ion exchange capacity, dimensional stability and alkali stability were prepared by a facile synthesis method. Internal crosslinking networks in the resulting membranes were achieved by reacting chloromethylated polysulfone with 4,4′-trimethylene bis(1-methylpiperidine) (BMP), where BMP was used as both a quaternization reagent and crosslinker without requirement of post-functionalization. In order to evaluate the alkali resistance and dimension stability performance of the resulting membranes, the molar ratio of BMP in the resulting membranes was fixed at four different contents: 40%, 60%, 80% and 100%. The obtained membranes were accordingly denoted as CAPSF-N, in which N = 40, 60, 80 and 100, respectively. Due to the dense internal network structure and spatial conformation of the six-membered rings, the resulting CAPSF-N AEMs showed enhanced dimensional structures (at 60 °C, the water uptakes and swelling ratios of CAPSF-N were 8.42% to 14.84% and 2.32% to 5.93%, respectively, whereas those for the commercial AEM Neosepta AMX were 44.23% and 4.22%, respectively). In addition, after soaking in 1 M KOH solution at 60 °C for 15 days, the modified membranes exhibited excellent alkaline stability. The CAPSF-100 membrane showed the highest alkali stability (retained 85% of its original ion exchange capacity and 84% of its original OH− conduction after the alkaline stability test), whereas the non-crosslinked APSF broke into pieces. Additionally, compared to the commercial Neosepta AMX membrane under the same test conditions, the desalination efficiency of CAPSF-100 was enhanced, and the energy consumption was lower.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2018
·Vol. 136
·期 16
·47395
·
IF 1.901
Xu Han,Jilin Wang,Lulu Wang
A series of anion exchange membranes [pyridine functionalized-poly(vinyl alcohol)-1,4-dichlorobutane (PVA-PY-DL x )] were synthesized by using PVA-PY as polymer matrix and DL as crosslinker and iodomethane as quaternization reagent. During the experiment, pyridine groups grafted on PVA were transformed into quaternary ammonium group during the formation process of the crosslinked structure and the quaternization routine by iodomethane. The characterization results revealed that the PVA-PY-DL x membranes have been successfully prepared and the crystallinity increases with increase of DL. PVA-PY-DL x membranes have smooth and uniform morphology. The introduction of crosslinked structure improves the mechanical properties and dimensional stability of the PVA-PY-DL x membrane, enhances the alkali resistance. When the mass content of DL was 4.0%, composite membrane had the maximum tensile strength (44.2 MPa), and the OH − conductivity reaches 1.05 × 10 −2 S cm −1 at 70 °C. The accelerated aging experiment was carried out in 3 mol L −1 potassium hydroxide (KOH) solution for 120 h at 80 °C, which revealed that the anionic conductivity of PVA-PY-DL 4.0 membrane retains 79.6% of its initial conductivity, showing better stability of alkali stability. Methanol permeability of PVA-PY-DL x membranes was only the 0.37–0.72% of the Nafion-117 membrane in 3 mol L −1 methanol at 60 °C. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47395.
研究领域:
高分子科学
·
材料化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
·
2018
·
IF 0
En Ning Hu,Chen Xiao Lin,Fang Hua Liu,Qian Yang,Ling Li,Qiu Gen Zhang,Ai Mei Zhu,Qing Lin Liu
To enhance the ionic conductivity and mechanical property of the chemically stable aliphatic anion exchange membranes (AEMs), cross-linked poly(vinylbenzyl chloride) AEMs (PVBC-xQ4) bearing long flexible cross-linker chains with multiple quaternary ammonium (QA) head were prepared via a facile one-step process. The AEMs exhibit high conductivity and excellent mechanical property. The cross-linked AEMs excluding any other heteroatomic bond especially the sulfone linkage or ether bond in the backbone have robust alkaline stability, low water uptake, and good dimensional stability. A well-developed hydrophilic/hydrophobic phase separated morphology was observed by atomic force microscopy (AFM) and transmission electron microscopy (TEM). The PVBC-50Q4 membrane with ionic exchange capacity (IEC) of 1.87 mequiv g–1 displays a highest ionic conductivity of 74.3 mS cm–1 at 80 °C. After tested in a 2 M aqueous KOH solution at 80 °C for 1300 h, 88% of the conductivity and 89% of the IEC were remained. Furthermore, a single cell using the PVBC-50Q4 membrane has a maximum peak power density of 109.2 mW cm–2 at 60 °C.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
RSC Advances
·
2019
·Vol. 9
·期 14
·7975-7983
·
IF 3.049
Dan Yao,Tonghui Wei,Lichao Shang,Hui Na,Chengji Zhao
Anion exchange membranes based on side-chain-type quarternized poly(ether ether ketone)s (QPEEKs), containing different hetero-cycloaliphatic quaternary ammonium groups, were prepared via a multi-step procedure, including polycondensation with a monomer containing pendant methylphenyl groups, bromomethylation, and followed by quaternization with 1-methylpyrrolidine (MPY), 1-methylpiperidine (MPRD), 1-methylimidazole (MIDZ) and N-methyl morpholine (MMPH), respectively. The properties of these membranes were then compared with the properties of conventional quarternized poly(ether ether ketone)s containing benzyltrimethylammonium (QPEEK-TMA). Model compounds, QMPY, QMPRD, QMIDZ and QMMPH, were synthesized and used to quantitatively compare the alkaline stability of hetero-cycloaliphatic quaternary ammonium groups using 1H NMR. The results of this study indicated that the alkaline stability of all these model compounds is in the order of QMPY > QMPRD > QTMA > QMIDZ > QMMPH. These QPEEKs membranes display superior thermal, dimensional and mechanical stability. QPEEK-TMA, QPEEK-MPY and QPEEK-MPRD exhibit higher hydroxide conductivities and lower activation energies than QPEEK-MIDZ and QPEEK-MMPH. Furthermore, after exposure to 1 M NaOH at 60 °C for 24 days, QPEEK-MPY and QPEEK-MPRD demonstrated a loss in hydroxide conductivity of 28.5% and 33.4%, respectively. Both values were lower than that of QPEEK-TMA (37.7%). Therefore, among these side-chain-type QPEEKs membranes, QPEEK-MPY and QPEEK-MPRD, containing benzylmethylpyrrolidinium and benzylmethylpiperidinium as cation head-groups, are promising AEM materials for fuel cell construction.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2019
·
IF 7.015
Jiafei Liu,Xiaoming Yan,Li Gao,Lei Hu,Xuemei Wu,Yan Dai,Xuehua Ruan,Gaohong He
To achieve a better performance of anion exchange membranes (AEMs), AEMs of a unique structure with flexible and dense side chains are prepared by taking amino groups on poly (aryl ether ketone)s (PAEKs) as reaction sites and grafting four long side chains on each repeat unit of main chains. This chemical synthetic route for the unique structure is simple and controllable, with no obvious side reactions happening during synthetic process. Three different kinds of cycloaminium cations are used as functional groups. The AEMs with this unique structure exhibit limited swelling ratios and improved hydroxide conductivities, of which the highest attains 74.4 mS cm −1 at 80 °C when using N-Methylmorpholine (Mm) as the cation group. The high conductivities are due to the formation of connective ion conducting channels facilitated by this kind of structure inside the membranes. No obvious changes in chemical structures of AEMs with different cations happen after alkali treatment for 768 h at 60 °C, indicating a good alkaline stability of AEMs with such specific structure. Moreover, the PAEK-MmOH yields a maximum power density of 302 mW cm −2 at 640 mA cm −2 when operating in a single fuel cell. Overall, these long-branched and densely functionalized AEMs with cycloaminium cation groups possess good application prospects in fuel cells.
研究领域:
材料科学
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化学工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2021
·
IF 4.43
Ziqin Li,Riming Yu,Chang Liu,Jifu Zheng,Jing Guo,Tauqir A. Sherazi,Shenghai Li,Suobo Zhang
The poly(aryl ether ketone) with spatial cardo structure is prepared from 4,4′-bis(phenoxy)benzophenone and 1-(4-bromobutyl)indoline-2,3-dione through a facile polyhydroxyalkylation reaction catalyzed by superacid . The number average molecular weight of the resultant polymer is achieved as high as 105.6 kg mmol −1 . Three anion exchange membranes were prepared by reacting the polymer with trimethylamine , N-methyl-piperidine, and N,N,N′,N′,N″-pentaethylguanidine, respectively. Among the prepared membranes, N-methyl-piperidine based anion exchange membrane exhibited the highest OH − conductivity of 99.8 mS cm −1 at corresponding IEC of 1.54 meq g −1 . In addition, the prepared membranes also exhibit excellent mechanical properties , in which the tensile strength and elongation at break can reach up to 50 MPa and 35%, respectively. Moreover, the anion exchange membranes exhibited good alkaline stability. When they were treated with 1 M KOH at 60 °C for 600 h, their conductivity decreased by less than 5%.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 49
·30770-30783
·
IF 3.108
Qian Shi,Pei Chen,Jinfang Zhou,Qiang Weng,Xueliang Zhang,Xinbing Chen,Zhongwei An
A new difluoro aromatic ketone monomer, (2,6-difluorophenyl)[3,5-bis[(3,5-dimethylphenyl)methyl]phenyl]methanone, is developed to prepare a series of poly(arylene ether sulfone)s (PAES) bearing two pendant 3,5-dimethylphenyl groups via polycondensation reaction. The desired side-chain type PAESs containing multiple benzyl quaternary ammonium groups (QPAES(x/y)) are obtained by the corresponding bromomethylation and subsequent quaternization. Their properties, such as hydroxide conductivity, dimensional change, water uptake and alkaline stability, are investigated. Side-chain type membranes QPAES(x/y) with ion exchange capacities (IECs) of 0.96–1.22 mequiv. g−1 display anisotropic membrane swelling and hydroxide conductivity of 39.9–49.8 mS cm−1 at 80 °C. The greater length and dense distribution of the benzyl-type quaternary ammonium pendants are probably responsible for the good hydroxide conductivity and alkaline stability. Meanwhile, the corresponding crosslinked membrane (CQPAES(1/4)) shows higher conductivity, lower membrane swelling, better oxidative stability and higher chemical stability in hot alkali solution (80 °C) than the uncrosslinked one with a comparable IEC value.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）