POLYMER
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2018
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IF 3.483
Cuihong Jin,Xiuling Zhu,Shuai Zhang,Shuai Li
In this work, a series of long flexible alkylsulfonated side chains poly (phthalazinone ether ketone) (SFG-PPEK-x) are successfully synthesized through polycondensation , demethylation , and sulfobutylation grafting reaction to the polymer backbone. The resulting ionomers could dissolve in polar aprotic solvents , such as DMSO , NMP etc and show excellent film-forming properties. Furthermore, the effect of side chain lengths on the properties of the resulting PEMs, such as proton conductivity, water uptake, and swelling ratio are investigated systematically. The SFG-PPEK-4 membranes (IEC = 1.70 mmol g −1 ) show the highest proton conductivity in the range of 107 mS cm −1 at 30 °C and 184 mS cm −1 at 80 °C, which is higher than that of Nafion ® 115. The thermal, mechanical properties and chemical stability of SFG-PPEK-x are discussed, systematically.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2023
·
IF 4.2
Jiafeng Qian,Shiju Cai,Jianxiong Hu,Chenyi Wang,Guang Li
In order to promote the conduction and stability of anion exchange membranes (AEMs) for the vanadium redox flow battery (VRFB), a kind of quaternary ammonium AEMs with flexible side chains (PAES-4N-xx, xx represents the proportion of monomers containing an amino structure) are prepared via aromatic nucleophilic polycondensation and grafting reactions. The ion exchange capacity (IEC) values of PAES-4N-xx are in the range of 1.58–2.10 mmol g–1, and their water uptake, swelling ratio, SO42– conductivity, and VO2+ permeability at 30 °C are in the range of 15–52%, 5–17%, 13.5–22.4 mS cm–1, and 8.6–43.3 cm2 min–1, respectively. In addition, PAES-4N-xx display good stability, and their retention ratio of IEC and conductivity reach more than 95% after soaking in a solution of 1.5 mol L–1 VO2+/3 mol L–1 H2SO4 at RT for 30 days. The typical battery assembled with PAES-4N-40 shows high efficiency; its Coulomb efficiency (CE), voltage efficiency (VE), and energy efficiency (EE) are in the range of 93.5%–97.8%, 88.6%–70.5%, and 69.0%–84.9% at the fixed current density which is between 40 mA cm–2 and 200 mA cm–2, respectively. The battery also has good stability for 100 cycles of charging and discharging at a current density of 40 mA cm–2, and its retention of EE reaches 96.5%. The introduction of flexible side chains and dense cationic structures can effectively improve the performance of the VRFB.
研究领域:
材料科学
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电化学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
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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
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燃料电池技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2018
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IF 8.097
Chen Xiao Lin,Hong Yue Wu,Ling Li,Xiu Qin Wang,Qiu Gen Zhang,Ai Mei Zhu,Qing Lin Liu
To achieve highly conductive and stable anion exchange membranes (AEMs) for fuel cells, novel triblock copolymer AEMs bearing flexible side chain were synthesized. The triblock structure and flexible side chain are responsible for the developed hydrophilic/hydrophobic phase separated morphology and well-connected ion conducting channels, as confirmed by transmission electron microscopy. As a result, the triblock copolymer AEMs with flexible side chain (ABA–TQA-x) demonstrated considerably higher conductivities, up to 130.5 mS cm–1 at 80 °C, than the AEMs with monocation side chain (ABA–MQA). Furthermore, the long alkyl spacer between the backbone and quaternary ammonium groups, as well as long intercation spacer limits the water swelling of the membranes to some degree, resulting in good alkaline stability. The ABA–TQA-44 membrane retained 84.7% and 83.1% of its original conductivity and ionic exchange capacity, respectively, after immersed in a 1 M aqueous KOH solution at 80 °C for 480 h. Furthermore, the peak power density of a H2/O2 single cell using ABA–TQA-44 is 204.6 mW cm–2 at a current density of 500 mA cm–2 at 80 °C.
研究领域:
材料科学
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能源化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
·
IF 7.312
Faizal Soyekwo,Changkun Liu,Yunxia Hu
Polymeric membranes are more practicable to the cost-effective and energy-efficient solvent recovery and molecular separation in solvent mixtures, but the construction of structure-defined chemically stable as well as high permeance polymer membranes for organic solvent nanofiltration (OSN) applications is an important challenge. Herein, we designed and constructed crosslinked block copolystyrene membranes containing flexible alkylcarboxylated and alkylsufonated side chains for high-separation performance in organic media. The flexible side chains anchored on the all-carbon network render the membranes with good dimensional flexibility due to the rational manipulation of the intermolecular and intramolecular bonding interactions within the crosslinked structured polymer chains. Depending on the crosslinking degree, the resultant membranes exhibited outstanding stability in polar protic solvents, mild polar aprotic solvents (THF, acetonitrile and acetone) and nonpolar solvents. Specifically, the CPS-24% membrane with a cutoff of 380 g mol −1 showed good ethanol permeance of 4.16 L m −2 h −1 bar −1 and a high-efficient molecular separation (>96%) of a broad range of small molecular weight solutes (organic dye molecules, organic building blocks and antibiotics). The membrane also achieved molecular level selectivity of two molecules with a mass difference down to 141 g mol −1 , which is attractive for molecular separation in the chemical and pharmaceutical industry. This work provides a promising strategy to improve selective solvent permeation and separation of organic molecules in OSN membranes by introducing flexible hydrophilic/hydrophobic side chain domains into the main backbone of rigid polymer structures.
研究领域:
材料科学
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化学工程
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膜技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
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IF 8.4
Yuanlong Wu,Jiaran Song,Tianxiang Zhao,Yunji Xie,Di Liu,Le Wang,Genyu Wei,Haidong Ma,Zhe Wang
In recent years, advancements in anion exchange membranes (AEMs) have notably enhanced the overall performance of anion exchange membrane fuel cells (AEMFCs). However, issues like limited alkali stability and low ionic conductivity of AEMs have become apparent. In this study, focusing on molecular design, a series of polycarbazole-based AEMs with flexible side chains, named PCP- n (where ‘ n ’ denotes the molar ratio of the newly synthesized monomer BHC in carbazole derivatives), were developed. The integration of long flexible side chains fosters chain movement and the clustering of piperidine cations, leading to distinct hydrophilic/hydrophobic nanoscale phase separation within the PCP- n membranes. Moreover, the PCP- n membranes demonstrate effective water management capabilities, with the PCP-90 membrane displaying a 32 % water uptake and an in-plane swelling ratio below 20 % at 80 °C. The introduction of an ether-free main chain based on carbazole derivatives along with the highly stable piperidine cationic group endows the PCP- n membranes with exceptional alkali resistance. Following a 1500-h immersion in 2 M KOH at 80 °C, the PCP-90 membrane successfully retains 79.92 % of its original ionic conductivity . Given its substantial thermal stability and mechanical strength , the PCP-90 membrane underwent testing in membrane electrode assembly and single-cell performance, achieving a notable peak power density of 275.64 mW cm −2 and an open-circuit voltage of 0.98 V. Overall, the impressive comprehensive performance of the PCP- n membranes suggests a promising future for their application.
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
SEPARATION AND PURIFICATION TECHNOLOGY
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2018
·
IF 3.927
Di Zhou,Guolong Rong,Sa Huang,Jinhui Pang
In order to mitigate the selectivity-permeability trade-off for ultrafiltration membranes, a series of polyphenylene sulfone (PPSU) with flexible negative charged sulfonated side chains (SPPSU-SC) were synthesized applied in ultrafiltration (UF) field. And tests results showed that the ultrafiltration performance was enhanced greatly. In short, the water flux increased to 380 L · m −2 · h −1 at the sulfonation degree of 20%, which was as two and a half times high as PPSU membranes. However, the membrane SPPSU-SC20 still held a relatively high BSA rejection of 91.6%, which should be attributed to the enrichment of negative charged sulfonic groups on the membrane surface. More importantly, the antifouling properties were also promoted. The total fouling ratio (R t ), reversible fouling ratio (R r ), irreversible fouling ratio (R ir ) and flux recovery ratio (FRR) were all improved to some degree. Besides, compared to the main-chain sulfonated PPSU with the sulfonation degree of 20% (SPPSU-MC20) membranes, SPPSU-SC20 had a better separation structure caused by better phase separation during the membrane preparation period at the sane high sulfonation degree. In a word, the results showed that side-chain sulfonated PPSU possessed a potential bright horizon in ultrafiltration field.
研究领域:
材料科学
·
化学工程
·
膜技术
✓ 已验证
产品关联
DOI
高影响因子
Materials Horizons
·
2023
·
IF 13.3
Ziwen Liu,Xiao Pang,Benbing Shi,Na Xing,Yawei Liu,Bohui Lyu,Leilang Zhang,Yan Kong,Sijia Wang,Zhong Gao,Rou Xue,Tianyu Jing,Changkun Liu,Qinhuidan Bai,Hong Wu,Zhongyi Jiang
Electrochemical hydrogen compression (EHC) is an emerging energy conversion technology. Proton exchange membranes (PEMs) with high proton conductivity and high mechanical strength are highly required to meet the practical requirements of EHC. Herein, ionic covalent organic frameworks (iCOFs) with tunable side chains were synthesized and introduced into the sulfonated poly (ether ether ketone) (SPEEK) matrix to fabricate hybrid PEMs. In our membranes, the rigid iCOFs afford ordered proton conduction channels, whereas the flexible side chains on iCOFs afford abundant proton conduction sites, adaptive hydrogen bonding networks, and high local density short hydrogen bonds for highly efficient proton transport. Moreover, the hydrogen bond interactions between the side chains on iCOFs and the SPEEK matrix enhance the mechanical stability of membranes. As a result, the hybrid PEM acquires an enhanced proton conductivity of 540.4 mS cm−1 (80 °C, 100%RH), a high mechanical strength of 120.41 MPa, and a superior performance (2.3 MPa at 30 °C, 100%RH) in EHC applications.
研究领域:
材料科学
·
化学工程
·
能源技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）