ADVANCED FUNCTIONAL MATERIALS
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2025
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IF 19
Yuting Wan,Penghao Hu,Binzhou Sun,Shuyi Shen,Hang Luo,Shujun Zhang,Dou Zhang,Ce-Wen Nan,Yang Shen
Dielectric polymers must exhibit low conductivity and thermal stability to realize high-performance capacitive energy storage under high-temperature conditions. However, conventional heat-resistant polymers suffer from deteriorated insulation at elevated temperatures, limiting their practical applications. Here, it is proposed and demonstrated that a self-driven thermal crosslinking approach, without crosslinker, is highly efficient in breaking the adverse correlation between the insulation and thermal stability of dielectric polymers at high temperatures. By decarboxylation-driven crosslinking within polyetherimide (PEI) molecular chains, a robust network is formed, effectively suppressing charge carrier migration. The synergistic combination of decarboxylation-induced structural densification and residual carboxyl-enabled deep charge trapping synergistically reduces the electrical conductivity of the modified PEI by 3 orders of magnitude relative to conventional polyimide (Kapton PI) at 250 °C. Consequently, a significantly enhanced discharge energy density of 3.7 J cm −3 with a charge-discharge efficiency of 91% is achieved at 250 °C, outperforming existing pure polymer dielectrics. Furthermore, the scalability of this approach is demonstrated by producing a 100-meter-long modified film through an industrial-scale roll-to-roll solution-casting process, highlighting its compatibility with mass production. This strategy also proves to be universal to other dielectric polymers to achieve high insulation and heat resistance at elevated temperatures.
研究领域:
材料科学
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能源工程
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2015
·
IF 5.056
Sheng Xu,Yan Wang
In this work, two novel carboxyl-containing polyimides , 2,2′-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride-4,4′-diaminodiphenylmethane/3,5-diaminobenzoic acid (6FDA-MDA/DABA, FMD) and 3,3′,4,4′-benzophenone tetracarboxylic dianhydride-4,4′-diaminodiphenylmethane/3,5-diaminobenzoic acid (BTDA-MDA/DABA, BMD), are synthesized via chemical and thermal imidization methods, respectively, and employed as pervaporation membranes for ethanol dehydration. Chemical structures of the two polyimides are examined by FTIR and TGA to confirm the successful synthesis. A post thermal treatment of the polyimide membranes with the temperature range of 250 to 400 °C is applied, and its effects on the membrane morphology and separation performance are studied and characterized by FTIR, TGA, WXRD, solubility and sorption test. It is believed that the thermal treatment of the carboxyl-containing polyimide membrane at a relative low temperature only leads to the physical annealing, while it may cause the decarboxylation-induced cross-linking at a higher temperature. In addition, the operation temperature in pervaporation is also varied and shown to be an important factor to affect the final membrane performance. Performance benchmarking shows that the developed polyimide membranes both have superior pervaporation performance to most other flat-sheet dense membranes. This work is believed to shed useful insights on polyimide membranes for pervaporation 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
Advanced Membranes
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2025
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IF 9.5
Bingbing Gao,Yiran Peng,Ming Wu,Hua Ma,Jianchao Sun,Peng Zhang,Xingzhong Cao,Like Ouyang,Xiaobin Fu,Chunfang Zhang,Yunxiang Bai,Lijun Liang,Yang Liu,Liangliang Dong
Polyimide membranes have attracted considerable attention for gas separation applications; however, achieving efficient helium (He) separation remains a significant challenge due to the low fractional free volume ( FFV ) and poorly controlled pore size distribution. Here, we report a novel three-in-one polyimide-based blended membrane constructed from a polymer (6FDA-TFMB) and alkynyl-based polyimide (EBPA-TB) matrix via thermal crosslinking. By carefully designing membrane synthesis and structure, the resulting membrane achieves the “1+1>2” effect: (i) high He selectivity derived from reinforced interphase adhesion and size-sieving ability due to the hydrogen bonding and similar structure between 6FDA-TFMB and EBPA-TB; (ii) high He permeability derived from the rigid cross-linked network distorting the EBPA-TB chain packing and generating additional free volume; (iii) high anti-aging performance derived from the thermal crosslinking preventing microstructural rearrangements. The optimal membrane an unprecedented combination of high He permeability (51.24 Barrer), excellent He/N 2 selectivity (146.40) and remarkable aging resistance (less than 3.97 % of permeability decrease over 50 days), outperforming the performance of state-of-the-art polyimide-based blended membranes for He purification. This three-in-one blended membrane construction strategy provides a general toolbox for the development of next-generation, high-performance blended membranes with desirable performance for diverse industrial applications.
研究领域:
材料科学
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化学工程
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气体分离技术
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DOI
高影响因子
Advanced Materials Interfaces
·
2021
·Vol. 8
·期 24
·2100458
·
IF 6.147
Xiaoyan Song,Zhen Wang,Fangzheng Zhao,Yizhe Sun,Bowen Cheng,Jinfeng Xing
In this study, a polyimide/aminopropyllsobutyl polyhedral oligomeric silsesquioxane (PI/A-POSS) membrane with a novel 3D thermal crosslinking structure is prepared by electrospinning and subsequent imidization. Compared with the pure PI membrane, PI/A-POSS composite membranes present better mechanical properties, narrower distribution of pore size, smaller average pore size, and better thermal stability. When A-POSS content is 3 wt%, the composite membrane (A3) has outstanding electrolyte uptake, excellent ionic conductivity, low interfacial resistance, and the high electrochemical stability of anode. The battery assembled with the A3 separator has an excellent first discharge capacity of 137.8 mAh g −1 and its capacity retention rate is still as high as 76.49% after 100 cycles at 2.0 C. Furthermore, battery assembled with the A3 separator shows excellent rate capacity with a relatively high discharge capacity up to 169.7 mAh g −1 at 0.2 C and a superior capacity recovery rate of 98.06% at 30 °C. Especially, the battery assembled with the A3 separator shows more prominent rate capacity with an excellent first discharge capacity up to 180.5 mAh g −1 at 0.2 C and a superior capacity recovery rate of 95.79% at 60 °C.
研究领域:
材料科学
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能源存储与转换
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Can Wang,Zhenyuan Li,Ju Bai,Hongyan Liu,Xinbo Wang,Shuangjiang Luo
Membrane-based helium recovery from natural gas faces a major challenge due to membrane plasticization, which increases permeances but reduces selectivities. Thermal crosslinking has emerged as a promising approach to enhance the plasticization resistance of membranes by restricting segmental mobility and creating well-defined microporosity for gas separation. Herein, we develop novel dual thermally crosslinked asymmetric hollow fiber membranes (HFMs) using a 4,4′-diamino-2,2′-biphenyldicarboxylic acid-containing copolyimide. Decarboxylation-based dual crosslinking is achieved through heat treatment at various temperatures, resulting in the generation of C–C covalent bonds. The interchain distance increases from 5.33 to 5.76 Å, and the hierarchical pore size distributions exhibit ultra-micropore size between 5.6 and 6.8 Å as well as micropore size between 7.0 and 9.5 Å. Notably, the formation of stable C–C covalent bonds through dual crosslinking and the existence of bulky −CF 3 groups in the 2,2′-bis(trifluoromethyl)-4,4′-biphenyldiamine moiety prevent substructure collapse by enhancing the chain rigidity and rotational barrier. Gas transport properties of the crosslinked HFMs are effectively tuned by adjusting the heat treatment temperatures. Particularly, the PI-TFMB-HF@400 membrane exhibits a He permeance of 25 GPU and He/CH 4 selectivity of 269. Additionally, the crosslinked HFMs exhibit enhanced plasticization resistance. The PI-TFMB-HF@400 membrane, for instance, shows only a 24 % decrease in mixed-gas CO 2 /CH 4 selectivity and an 80 % increase in mixed-gas [He/(CO 2 + CH 4 )] selectivity when exposed to a high-pressure (40 bar) ternary mixed-gas feed of He/CO 2 /CH 4 (0.3/49.7/50, v/v/v), and the mixed-gas [He/(CO 2 + CH 4 )] selectivity increases with temperature. The dual thermally crosslinked HFMs in this study demonstrate the potential for helium recovery from aggressive natural gas.
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
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2022
·
IF 10.53
Can Wang,Zhili Cai,Wei Xie,Yang Jiao,Lu Liu,Lili Gong,Qi-Wei Zhang,Xiaohua Ma,Hongjun Zhang,Shuangjiang Luo
Thermally induced chemical crosslinking has attracted substantial attention for fabricating plasticization resistant membranes due to the facile structure tunability that enables the construction of robust and well-defined architecture for gas separation. In this study, we report a new series of dual thermally crosslinkable polyimides derived from 4,4′-diamino-2,2′-biphenyldicarboxylic acid (DCB) containing two carboxyl groups, and a systematic investigation of the thermal treatment above and below T g demonstrated the decarboxylation-induced crosslinking. The dual thermally crosslinked membranes were insoluble in common organic solvents and maintained excellent mechanical properties . Due to the evolution of CO 2 and collapse of chain segments during thermal treatment, the crosslinked membranes exhibited hierarchical microcavity size distribution featuring ultra-micropore size in the range of 2.0–6.0 Å and micropore size in the range of 6.5–10.0 Å. Gas transport properties of the crosslinked membranes were feasibly tuned through the chemical compositions and thermal treatment procedures. For instance, the CO 2 permeability of crosslinked 6FDA-DAM 0.7 -TFMB 0.1 -DCB 0.2 increased almost three-fold with only a slight decrease in CO 2 /CH 4 selectivity. The crosslinked membranes also demonstrated superior plasticization resistance with mixed-gas feed pressure up to 40 bar and excellent low-temperature gas separation performance at −30 °C, making them attractive for aggressive gas separations.
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
CHEMICAL ENGINEERING SCIENCE
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2024
·
IF 4.1
Hua Ma,Haohao Liu,Feng Tian,Bingbing Gao,Lijun Liang,Yang Liu,Peng Gao,Xingzhong Cao,Yunxiang Bai,Chunfang Zhang,Liangliang Dong
Membrane separation technology plays a critical role in the utilization of helium (He) resources. Yet, the performance of current polymer membranes is hindered by a trade-off between permeability and selectivity, as well as by physical aging. Solving these problems is vitally crucial for the industrial application of He separation. This study reported controllable thermal crosslinking of alkynyl-based polyimide membrane (EBPA-TB-TC) to improve He permeability and anti-aging performance. The resulting covalently crosslinked structures conferred thermal and chemical stability to the membranes, as well as increased microporosity. It led to a notable 'anti-trade-off' effect and improved anti-aging characteristics. An optimized EBPA-TB-TC membrane exhibited a superior combination with a He permeability of 61.14 Barrer and an He/N 2 selectivity of 72.78. Crucially, mixed-gas He/N 2 (1:1, 50/50) separation results over 50 days revealed minimal reductions in He permeability (1.34 %) and He/N 2 selectivity (2.95 %), indicating fantastic anti-aging performance. These findings demonstrated the significant potential of thermally cross-linked EBPA-TB-TC membrane in long-term stable helium separation.
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
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2021
·
IF 8.742
Jingjing Kong,Junjie Liu,Peiyu Jia,Ning Qi,Zhiquan Chen,Shan Xu,Nanwen Li
Two kinds of polyimide membranes 6F-AP and 6F-AP/DA (APAF:DABA=3:2) were synthesized and heated between 300–450 °C to study the effect of thermal treatment on the chain structure and gas transport performance of membranes. Fourier Transform Infrared (FI-IR) and X-ray diffraction (XRD) measurements show that heating causes rearrangement of polyimide into rigid polybenzoxazole which prevents the effective stacking of polymer chains leading to the increase of d-spacing and fractional free volume. Positron annihilation results confirm the increase of both size and number of free volume due to the thermal rearrangement. The addition of DABA monomer into 6F-AP causes crosslinking during heating, which results in tightening of the rigid chain spacing of benzoxazole, thus leading to slight decrease in the size and number of free volume. The increase in fraction free volume induced by thermal rearrangement can significantly improve the gas permeability of 6F-AP series membranes, which increases from 16.2 and 3.9 barrer to 271.4 and 200.3 barrer for H 2 and CO 2 , respectively, after increasing the heating temperature from 300 to 450 °C. But this is accompanied by a decrease in gas selectivity due to the increase in free volume size. Finally, by careful tailoring the free volume structure through thermal rearrangement and crosslinking, the 6F-AP/DA polyimide treated at 400 °C exhibits a H 2 permeability of 196.4 barrer and a H 2 /CH 4 ideal selectivity of 90, which is above the 2008 Robeson upper bound. Our results indicate that by designing the functional groups of the reaction monomer plus appropriate thermal treatment, the microstructure of polyimide membrane can be effectively adjusted for high-performance gas separation.
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
TEXTILE RESEARCH JOURNAL
·
2024
·
IF 1.6
Xianhua Zhang,Hewei Xiang,Mengyu Yuan,Jie Liu,Yingxue Pei,Yanchao Zhao,Haozhe Tang,Fan Liu
We report a facile strategy for preparing ultralight, mechanically robust, and washable heat-retaining materials via solution blow spinning technology and thermal crosslinking. Fluffy microfibrous assemblies with nonwoven structure were fabricated by blending fibers of stiff and soft polymers and creating a bonding architecture among them. The premise of this design is that polystyrene, which is stiff, can endow materials with rigidity, while thermoplastic polyurethane, which is soft, can absorb energy during mechanical deformation. Moreover, the stability of the sponge was improved by using tris (2-methyl-1-aziridine propionate; TTMA) as a crosslinking agent. The optimized microfibrous sponges present excellent mechanical properties with a large breaking elongation of 42.1% and outstanding resilience in resisting 100 cyclic compressions at 40% strain. Furthermore, the microfibrous sponges exhibit a low volume density of 33.32 mg/cm3, effective heat-preservation ability (low thermal conductivity: 23.1 mW/m·K) and excellent washability. The preparation of microfibrous sponges via solution blow spinning can be a novel route for developing ultralight and superelastic heat retention materials.
研究领域:
材料科学
·
纺织工程
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DOI
高影响因子
JOURNAL OF POLYMER SCIENCE
·
2020
·Vol. 58
·期 20
·2951-2962
·
IF 0
Kai Ma,Guofei Chen,Yonggang Zhang
A series of cross-linked polyimides (PIs) were prepared via two-step solution polycondensation from 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride (BPADA) and 2,5-furandicarboxylic acid-based diamines, N,N ′-bis(4-amino-2-(trifluoromethyl)phenyl)furan-2,5-dicarboxamide (TFFDA) and N,N ′-bis(4-aminophenyl)furan-2,5-dicarboxamide ( p -FDDA), followed by thermal crosslinking reaction with bismaleimide. The thermal crosslinking reaction and its mechanism were studied by FTIR spectra and model reaction analysis, which showed Diels–Alder reaction between furan group and maleimide group played a main role in the thermal treatment. The properties of cross-linked PIs were characterized using dynamic mechanical thermal analysis, thermogravimetric analyses, tensile testing, ultraviolet-visible spectra, and wide-angle X-ray diffraction. The cross-linked polyimide film showed improved solvent-resistance, thermal and mechanical properties with T g values of 234–306 o C, tensile strengths of 82–98 MPa and moduli of 2.3–3.0 GPa. Graphical Several cross-linked polyimides (PIs) were prepared via polycondensation of dianhydride and 2,5-furandicarboxylic acid (2,5-FDCA)-based diamines, N,N ′-bis(4-amino-2-(trifluoromethyl)phenyl)furan-2,5-dicarboxamide, and N,N ′-bis(4-aminophenyl)furan-2,5-dicarboxamide, and following thermal crosslinking reaction with bismaleimide. These PIs exhibit outstanding thermal and mechanical properties. The crosslinking network of 2,5-FDCA-based PIs and bismaleimide is constructed for the first time by Diels–Alder reaction. The thermal crosslinking mechanism is also studied in detail using model reaction.
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
MOLECULES
·
2023
·Vol. 28
·期 5
·2173
·
IF 4.6
Xiyu Song,Chen Wang,Xiangyu Gao,Yao Wang,Rui Xu,Jian Wang,Peng Li
The weak bonding energy and flexibility of hydrogen bonds can hinder the long-term use of hydrogen-bonded organic framework (HOF) materials under harsh conditions. Here we invented a thermal-crosslinking method to form polymer materials based on a diamino triazine (DAT) HOF (FDU-HOF-1), containing high-density hydrogen bonding of N-H⋯N. With the increase of temperature to 648 K, the formation of –NH– bonds between neighboring HOF tectons by releasing NH3was observed based on the disappearance of the characteristic peaks of amino groups on FDU-HOF-1 in the Fourier transform infrared (FTIR) and solid-state nuclear magnetic resonance (ss-NMR). The variable temperature PXRD indicated the formation of a new peak at 13.2° in addition to the preservation of the original diffraction peaks of FDU-HOF-1. The water adsorption, acid-base stability (12 M HCl to 20 M NaOH) and solubility experiments concluded that the thermally crosslinked HOFs (TC-HOFs) are highly stable. The membranes fabricated by TC-HOF demonstrate the permeation rate of K+ions as high as 270 mmol m−2h−1as well as high selectivity of K+/Mg2+(50) and Na+/Mg2+(40), which was comparable to Nafion membranes. This study provides guidance for the future design of highly stable crystalline polymer materials based on HOFs.Keywords:hydrogen-bonded organic framework (HOF);thermally crosslinked;ion separation
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
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
HaoJun Tian,Jiangzhou Luo,Xiangyun Liu,Xueping Zong,Song Xue
PIM-1 thin film composite (TFC) membrane has attracted great attention for organic solvent nanofiltration (OSN) because of its high porosity and excellent solution process-ability. However, the PIM-1 thin selective layer may swell excessively in polar solvents such as methanol and acetone, and thus it makes the connection between the PIM-1 selective layer and the porous support unstable, which can significantly impair its separation performance. In this work, a series of novel PIM-1 TFC membranes was obtained by spin-coating of PIM-1/tetrahydrofuran solution onto α-Al 2 O 3 ceramic supports followed by a thermal treatment process. Since the nitrile group within PIM-1 tends to experience a thermal crosslinking reaction forming stable triazine rings after heat treatment, thus the organic solvent resistance ability of PIM-1 TFC membrane was greatly enhanced. Results showed that the thermally treated PIM-1 TFC membranes possess better chemical stability in polar solvents and acceptable permeances for various solvents (e.g., 2 ∼ 4.2 L·m −2 ·h −1 ·bar −1 for methanol, and 4.3 ∼ 6.8 L·m −2 ·h −1 ·bar −1 for toluene). For instance, the PIM-1 TFC membrane termed as PIM-1-3 wt%-1h TFC showed a methanol permeance of 3.8 L·m −2 ·h −1 ·bar −1 with a rejection of 96.5% towards Congo red (M w = 697 Da). Moreover, compared to the pristine PIM-1 TFC membrane, the thermally treated PIM-1 TFC membrane possesses better separation stability after the long-term static immersion test in acetone and DMF for 7 days, and it also exhibit good stability in the continuous filtration test using 20 mg·L −1 Congo Red methanol solution, demonstrating a promising outlook in OSN fields.
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）