JOURNAL OF MEMBRANE SCIENCE
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2020
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IF 7.183
Yu Zhang,Won Hee Lee,Jong Geun Seong,Joon Yong Bae,Yongbing Zhuang,Shichao Feng,Yinhua Wan,Young Moo Lee
Even with high permeability, insufficient selectivity of intrinsically microporous polyimides is a major obstacle for large-scale membrane-based separation applications. The present work proposes to increase hydrogen separation performance by incorporating deliberately chosen alicyclic segments into Tröger's Base (TB)-based polyimide backbones via copolymerization . The resulting TB-based copolyimides showed the best hydrogen separation performance ( e.g., H 2 /CH 4 , H 2 /N 2 and H 2 /CO 2 ) among all state-of-the-art TB-based polyimide materials reported to date. An important contribution of enhancement in solubility selectivity to increase hydrogen separation performance was investigated for the first time in this study. The introduction of alicyclic segments significantly promoted the Langmuir affinity parameters of H 2 , thereby improving H 2 solubility over other gas solubilities (CH 4 , N 2 and CO 2 ). Herein, the unique backbone architecture highlights the possibility of accessing membranes characterized by favorable hydrogen separation performance in adverse/harsh environments, as well as by solution processability, desirable physical properties for large-scale 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
APPLIED SURFACE SCIENCE
·
2019
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IF 5.155
Jin-Ju Chen,Qi An,Raul D. Rodriguez,Evgeniya Sheremet,Yan Wang,Enrico Sowade,Reinhard R. Baumann,Zhe-Sheng Feng
Metallized polyimide (PI) film has great applications in the field of flexible electronics. Surface property adjustment is considered as an effective way to realize the metallization of PI film by chemical methods . In this work, we demonstrate a facile approach to fabricate metallized PI film via surface modification and electroless plating . Polyethyleneimine (PEI) cross-linked with glutaraldehyde (GA) is used as a modifier to act on the surface of alkali-treated PI film, and a special regular morphology is obtained. This PEI-modified PI film possesses not only functional groups for chemical bonding but also large surface roughness for mechanical locking with metallic copper layer. The resulting copper layer has low resistivity (2.30 μΩ·cm) and satisfactory adhesion to PI film (the highest score of 5B according to ASTM D3359), and the metallized PI sample exhibits reliable flexibility. These results demonstrate a promising potential of this approach in the field of PI film metallization with impact in wearables, light-weight, and flexible electronics.
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 Materials Chemistry C
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2020
·Vol. 8
·期 42
·14886-14894
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IF 7.059
Chao Huang,Jinhui Li,Deliang Sun,Rui Xuan,Yuying Sui,Tingyu Li,Liang Shang,Guoping Zhang,Rong Sun,Ching Ping Wong
Over the last few years, low-temperature curing polyimide (PI) has turned out to be a significant target for the advanced electronic package. Although the curing accelerators have been confirmed to be capable of significantly decreasing the curing temperature, their effects on properties have not been comprehensively examined. In this study, polyamide acid is synthesized by pyromellitic dianhydride (PMDA) and 4,4′-oxydianiline (ODA), and the process of low-temperature imidization is investigated by introducing six accelerators, i.e., quinoline (QL), isoquinoline (IQL), 2-methyl quinoline (2-QL), 4-methyl quinoline (4-QL), 8-methyl quinoline (8-QL), as well as 5,6,7,8-tetrahydroquinoline (THQL). As revealed from the results, the polyimide films formed using 4-QL and QL have exhibited prominent mechanical, thermal, and electrical properties. For the PI-4-QL, the tensile strength is 151.87 MPa, elongation-at-break reaches 161.36%, and the weight loss of 5% is observed at 533 °C; for the PI-QL, the tensile strength is 134.82 MPa, elongation-at-break reaches 145.16%, and the weight loss of 5% reaches 545 °C. As indicated from the results, the boiling point, acidity and molecular structure of the low-temperature curing accelerators show significant effects. Lower acidity and steric hindrance between the accelerator and amide bond facilitate the low-temperature imidization of polyamide acid. Furthermore, the as-prepared low-temperature cured PIs of 4-QL and QL would exhibit wide applications in advanced packaging industry.
研究领域:
材料科学
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电子工程
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DOI
高影响因子
EUROPEAN POLYMER JOURNAL
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2018
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IF 3.741
Zheng Lu,Jiang-Huai Hu,Chang Chen,Wei-Feng Peng,Zheng-Zhou Liu,Yang Liu,Ke Zeng,Gang Yang
To broaden the application of polyimide materials, adenine-based polyimide/nano-silica hybrid films were prepared via sol-gel method without using coupling agents. Adenine-based diamine, 9,10-bis(4-aminopheny)adenine ( p -APA), was introduced to polymerize with 3,3′,4,4′-tetracarboxydiphthalic ether dianhydride (ODPA) to synthesize polyimide (API) matrix. The compatibility between the polymer matrix and silica was improved by hydrogen bonding between NH group in p -APA and Si OH group in silica. Systematic studies showed that API hybrid films possess high transparency and outstanding thermal properties even though the doping content was up to 20 wt% (glass transition temperature ( T g ): 328 °C, maximum decomposition occurring temperature ( T max ): 603 °C (N 2 ), coefficient of thermal expansion (CTE): 16.60 ppm/ o C).
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
COMPOSITE STRUCTURES
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2020
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IF 5.138
Panpan Zhang,Ke Zhang,Xi Chen,Shuliang Dou,Jiupeng Zhao,Yao Li
With the development of high-frequency and high-speed flexible circuit boards, there are growing demands for low dielectric constant materials with high mechanical and electric breakdown strength . Herein, a novel sandwich structure is successfully fabricated using fluorinated graphene/polyimide (FG/PI) composite film as a dense outer surface layer and porous PI film as the middle layer. The middle porous layer lead to the ultra low dielectric constant. The presence of FG/PI layers resulted in the increase of mechanical and dielectric breakdown performance compared to that of porous PI. Especially, the three-layer FG/ PI film showed a tensile strength of 65.76 MPa, a tensile modulus of 2.96 GPa, a characteristic breakdown strength of 170.49 kV/mm, a dielectric constant of 1.92, and a dielectric loss of less than 0.003. Therefore, the sandwich structure PI film is a highly prospective candidate as flexible circuit substrates for electronics and microelectronics devices.
研究领域:
材料科学
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电子工程
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DOI
高影响因子
HIGH PERFORMANCE POLYMERS
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2018
·
IF 1.047
Songlv Qin,Shihui Qiu,Mingjun Cui,Zhendong Dai,Haichao Zhao,Liping Wang
Polyimide (PI)/graphene oxide (GO) nanocomposites with different loads of polydopamine-modified graphene oxide (PI/PDA-GO) were prepared. Meanwhile, the as-prepared PI/PDA-GO nanocomposites were compared with pure PI in terms of their morphologies, thermal and mechanical properties. Only a minor mass fraction of PDA-GO was required to enhance the mechanical and thermal properties of PI. The tensile strength of 1 wt% PDA-GO/PI was increased by 12% and the tensile modulus of 1 wt% PDA-GO/PI nanocomposites was increased by 25% compared to those of pure PI. Vickers hardness of the PI hybrid films increased with PDA-GO load and the maximum enhancement in Vickers hardness was observed at 2 wt% PDA-GO loading. On the other hand, the storage modulus of 1 wt% PDA-GO/PI was increased by 54% than that of neat PI. In consideration of the facile preparation of PDA-coated GO, superior physical properties over neat PI, PI/PDA-GO nanocomposites showed promising applications as functional films or composites.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
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IF 13.2
Qiang Wang,Xin Li,Mengxin Kan,Hui Gao,Shanshan Liu,Xingxiang Ji,Handong Mu,Zhuangzhuang Mao,Zhanhui Yuan
Shape memory polyimide (SMPI) has excellent thermal stability and chemical inertness, and was used in high-end applications, such as aerospace, microelectronics, etc. However, the unsatisfied strength and toughness is currently the key challenges of SMPI. Herein, lignin, a natural polymer, with abundant rigid benzene ring structures and reactive functional groups is used to enhance SMPI’s mechanical properties and shape memory performance. The formation of hydrogen bonds and π-π interactions between lignin and SMPI matrix resulted in the simultaneously enhancement of strength and toughness through in-situ polymerization. As a result, the tensile strength and strain of composite films is increased from 73.45 MPa and 5.2 % to 114.5 MPa and 90.2 % at lignin content of 4 wt%, which are remarkably increased by 156 % and 1734 %, respectively. The shape recovery triggering temperature decreases ∼ 7°C with the increase of lignin content. What’s more, the shape fixation rate ( R f : 99.8 %) and recovery rate ( R r : 100 %) of L/SMPI composite films was also improved, and various complex shapes can be molded. The good thermal stability was well maintained, in which the decomposition temperature ( T d ) is ∼ 507 °C and the glass transition temperature ( T g ) is ∼ 181 °C. The excellent performance of lignin-modified shape memory polyimide (L/SMPI) opened a new ear for high value application of natural polymer, particularly in shape memory material.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
高影响因子
APPLIED THERMAL ENGINEERING
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2019
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IF 4.026
Desong Fan,Ming Jin,Jun Wang,Jinhui Liu,Qiang Li
Thermal dissipation has become a vital issue in electronic devices with highly miniaturization and integration. As a high thermal conduction material, graphite has been used widely in these devices. However, heat dissipation of graphite is limited by the poor thermal radiation in serving as a heat sink. In this work, we proposed a novel composite foil with a sandwich structure of graphite-silver-polyimide, exhibiting high thermal conductivity and excellent selective emission property, which is attractive for application in outdoor space. The heat dissipation performance of the foil was numerically and experimentally investigated. Our simulations confirmed that employing a selective thermal emitter in the sandwich structure prevented object surface from overheating under direct sunlight, augmenting the dissipated heat generated by heat source, reducing the local high temperature of surface. By the solar simulator and infrared camera, we experimentally demonstrated the numerical prediction that the heat dissipation ability of sandwich structure is much better than the graphite.
研究领域:
材料科学
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电子工程
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产品关联
DOI
高影响因子
DYES AND PIGMENTS
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2017
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IF 3.473
Haiwei Tan,Hongyan Yao,Ying Song,Shiyang Zhu,Huaxuan Yu,Shaowei Guan
In this work, a novel tetra-amine, bis (4-(3, 5-bis (4-amino-2-(trifluoromethyl) phenoxy) phenoxy) phenyl) methanone, was synthesized and then utilized to produce hyperbranched polyamic acids via polycondensation with 4, 4’-(hexafluoroisopropylidene) diphthalic anhydride (6FDA). The resulting hyperbranched polyamic acids underwent termination by (4-amino) phenyl ferrocene and imidization, leading to ferrocene-terminated hyperbranched polyimide (HBPI-Fc). The resulting HBPI-Fc displayed superior solubility in conventional organic solvents and excellent thermal stability. A memory device with a configuration of indium tin oxide (ITO)/HBPI-Fc/Al was fabricated, in which the HBPI-Fc acted as the active layer. The device exhibited bistable electrical conductivity switching and nonvolatile bipolar write-once-read-many-times memory character with two threshold voltages of 2.2 V and −2.6 V, respectively, during positive and negative voltage sweep. The device exhibited an ON/OFF current ratio of 10 4 under a constant bias of −1.0 V and good stability in both ON- and OFF-state during the test period of 10 4 s. The revealed electrical bistability of the HBPI-Fc was found mainly due to the effective charge trapping effect of the electroactive terminal ferrocene groups.
研究领域:
材料科学
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电子工程
·
有机化学
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DOI
高影响因子
APPLIED SURFACE SCIENCE
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2017
·
IF 3.387
Haitao Huang,Jiayu Yu,Hanxiang Guo,Yibo Shen,Fan Yang,Han Wang,Rong Liu,Yang Liu
On the basis of the outstanding fouling resistance of zwitterionic polymers, an antifouling ultrafiltration membrane was fabricated through phase inversion induced by immersion precipitation method, directly using the novel zwitterionic polyimide (Z-PI), which was synthesized via a two-step procedure including polycondensation and quaternary amination reaction, as membrane material. The chemical structure and composition of the obtained polymer were confirmed by using FTIR, 1 H NMR and XPS analysis, and its thermal stability was thoroughly characterized by TGA measurement, respectively. The introduction of zwitterionic groups into polyimide could effectively increase membrane pore size, porosity and wettability, and convert the membrane surface from hydrophobic to highly hydrophilic. As a result, Z-PI membrane displayed significantly improved water permeability compared with that of the reference polyimide (R-PI) membrane without having an obvious compromise in protein rejection. According to the static adsorption and dynamic cycle ultrafiltration experiments of bovine serum albumin (BSA) solution, Z-PI membrane exhibited better fouling resistant ability, especially irreversible fouling resistant ability, suggesting superior antifouling property and long-term performance stability. Moreover, Z-PI membrane had a water flux recovery ratio of 93.7% after three cycle of BSA solution filtration, whereas only about 68.5% was obtained for the control R-PI membrane. These findings demonstrated the advantages of Z-PI membrane material and aimed to provide a facile and scalable method for the large-scale preparation of low fouling ultrafiltration membranes for potential applications.
研究领域:
材料科学
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环境工程
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生物医学工程
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DOI
高影响因子
Energy Technology
·
2017
·Vol. 6
·期 2
·326-332
·
IF 2.789
Ailian Wang,Hao Xu,Fulin Liu,Xu Liu,Shi Wang,Qian Zhou,Jie Chen,Shiyong Yang,Liaoyun Zhang
A new solid polymer electrolyte composed of a polyimide matrix, an ionic liquid additive (1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, [Bmim][TFSI]), and a lithium salt (lithium bis(trifluoromethanesulfonyl)imide, LiTFSI) is fabricated by the solution-casting technique. The obtained self-standing polyimide (PI)-based polymer electrolyte (PI-100 %BmimTFSI-60 %LiTFSI) membranes show a great flexibility, transparency, and infiltration ability. As a result of the high thermal stability of the polyimide matrix, the thermal decomposition temperature of the electrolyte is high (420 °C). The ionic conductivity can be up to 1.73×10 −5 S cm −1 at room temperature and reaches 1.26×10 −3 S cm −1 at 80 °C. In addition, the PI-100 %BmimTFSI-60 %LiTFSI electrolytes have a wide electrochemical stability window of 4.8 V, a general lithium ion transference number of 0.12, and good interfacial stability and compatibility. In particular, the assembled LiFePO 4 /Li half cells made from this polyimide-based electrolyte can light up a light-emitting diode lamp at room temperature.
研究领域:
材料科学
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电化学
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能源存储
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产品关联
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 102
·58252-58259
·
IF 3.708
Peng Yan,Bin Zhou,Ai Du
Polyimide cross-linked silica gels with different weight percentages of solid precursors and different volumes of MTMS were prepared by using bis(trimethoxysilylpropyl)amine (BTMSPA) cross-linked polyamide acid, synthesized by 4,4′-oxydianiline (ODA), p-phenylenediamine (PPDA) and biphenyl-3,3′,4,4′-tetracarboxylic dianhydride (BPDA), compounding with a silica network which was hydrolysed by MTMS, then supercritically dried to produce a hybrid aerogel. The obtained aerogels exhibit striking properties such as low density (as low as 90 mg cm−3), a large surface area (up to 582 m2 g−1), lower shrinkage (up to 20%) and are more easily accessible than those previous reported. Formulations made of 8.7% and 11.72% solid precursors never collapsed under compression. Furthermore, the latter shows the maximum modulus (up to 17 MPa) and a higher sound absorption coefficient (more than 0.8) with a thickness of 3 cm in a specific range of frequencies.
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
危险品化学品经营许可证（带存储）