ACS Applied Polymer Materials
·
2023
·
IF 5
Qili Zhou,Wen Wang,Yu He,Zhangcheng Li,Ruolan Zhao,Guangming Tao,Bin Hu,Chong Hou
Aerogels exhibit excellent sensing performance thanks to their high porosity, large specific surface area, and remarkable mechanical property. However, the prevalent aerogel-based analyzers fail to detect liquid in a way of low detection limit, fast response, and good robustness. Here, we have fabricated a polyimide aerogel (PIA) film with porosity up to 98.01% and thickness about 220 μm and built a liquid analyzer with this PIA film as a tribo-negative layer. The liquid analyzer can respond to different liquid droplets on the basis of liquid–solid interaction and the triboelectric effect. Benefitting from the mesoporous structure, high porosity, low thickness, and stable compression performance of the PIA film, the liquid analyzer shows fast response and good robustness for detecting different liquids down to 7 μL. The mechanisms of the analyzer for distinguishing liquids are discussed from the aspects of effective relative permittivity, the interaction between liquid and PIA film, and transfer charge quantity. The trace liquid analyzers based on high-performance PIA films provide support for the development of environmental protection and biochemical sensing and show huge application potential in sensing related areas.
研究领域:
材料科学
·
环境科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2023
·
IF 6
Bo Xu,Rui Feng,Tingting Zhao,Ling Zhou,Yanyun Ju,Jiaqi Chen,Qimeng Zhang,Lijie Dong
High-performance polyimide (PI) films with excellent ultraviolet (UV)-resistant radiation and low dielectric constant ( k ) properties are ideal spacecraft antenna substrates in space applications. However, conventional commercial PI films like Kapton® applied in the aerospace field are inevitably subjected to the harsh UV radiation environment, leading to their structural damage and performance failure. Herein, a type of “self-sacrificial” micro-branched crosslinked PI films were fabricated by employing tris(4-aminophenyl)amine (TAPA) intrinsically containing the C-N bonds to crosslink linear pure fluorinated PI (FPI), where TAPA functioned as the dual roles of crosslinker and creating “self-sacrificial” local deep traps of C-N bonds in crosslinked sites. Consequently, abundant local deep traps of C-N bonds in crosslinked sites could capture energy from UV-rays to prevent the destruction of PI molecular main chains, thus the crosslinked FPI-TAPA films exhibited better UV-resistant radiation properties than that of pure FPI films and commercial PI films. And the crosslinked film showed least k of 2.53 and least dielectric loss of 0.006 at frequency of 1 MHz owing to the introduction of micro-branched crosslinked structure. Additionally, a high breakdown strength of 522 MV/m, as well as a high tensile modulus of 3.03 ± 0.07 GPa, was achieved, much better than the value of pure FPI film. This work provides a novel and facile approach to fabricate high-performance PI films with excellent UV-resistant properties, exhibiting great potential application in aerospace and microelectronics industries.
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN POLYMER JOURNAL
·
2023
·
IF 6
Yuanzhen Xu,Mengru Zhang,Yuanyuan Pang,Tianyue Zheng,Chun Tian,Zhen Wang,Jingling Yan
Colorless polyimide (CPI) copolymers were synthesized by one-step or two-step methods, using 2,2′-bis(trifluoromethyl)benzidine (TFMB), 2,2′,3,3′-biphenyltetracarboxylic dianhydride (3,3′-BPDA), and 3,3′,4,4′-biphenyltetracarboxylic dianhydride (4,4′-BPDA) as the monomers . These polymers exhibited a d -spacing value of 5.7–6.7 Å, and their d -spacing values increased while the intensity of π-π stacking interactions decreased with the increase of 3,3′-BPDA/TFMB contents. The solubility of the copolymers were gradually enhanced as the increase of 3,3′-BPDA/TFMB contents. Their coefficients of thermal expansion and glass transition temperatures increased with 3,3′-BPDA/TFMB contents, ranging from 15 to 68 ppm K −1 and 300 to 359 °C, respectively. These polymers exhibited excellent optical transparency ( λ 0 < 390 nm, T 450 > 83.2%, and b* < 4). CPI-4 and CPI-5 with 40 mol% and 20 mol% of 3,3′-BPDA/TFMB contents exhibited well-balanced solution processability and physical properties. The CPI copolymers can be potentially used in optical and optoelectronic fields owing to their desirable overall properties.
研究领域:
材料科学
·
聚合物化学
✓ 已验证
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2024
·
IF 8.1
Fan Wang,Xiaodi Dong,Guangyi Liu,Baoquan Wan,Jinghui Gao,Baixin Liu,Jun-Wei Zha
Polyimide (PI) is widely used in electronic, electrical and communication fields because of its outstanding mechanical properties, electrical insulation and thermal stability. However, the lower thermal conductivity limits their application. Here, PI composite films with high thermal conductivity are obtained by utilizing reactive groups on the carbon nitride nanosheets (CNNS) surface to form covalent bond with PI matrix. The thermal conductivity of CNNS/PI composite films can reach 5.84 W∙m −1 ∙K −1 , which is about 10 times higher than that of pure PI (0.56 W∙m −1 ∙K −1 ). This is attributed to the covalent bond between CNNS and PI matrix acting as a “thermal bridge” to connect the discontinuities at the interface, thereby reducing the interfacial thermal resistance between CNNS and PI. The heat transfer mechanism of composite film is further revealed by finite element analysis . This work provides a viable solution to improve the thermal conductivity of PI, allowing for a wide range of potential applications for PI in electronic devices.
研究领域:
材料科学
·
热物理学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Polymer Materials
·
2024
·
IF 4.4
Xiaojuan Feng,Hongyan Wang,Lingxiao Yan,Chaonan He,Yu Chen,Song Xue,Qiang Liu
High-performance polymeric separators are indispensable materials for advanced rechargeable lithium-ion batteries (LIBs). In general, separators must simultaneously possess the following qualifications: flame retardancy, mechanical strength, wettability, and ion conductivity. In this paper, a siloxanediamine, namely, 1,3-bis(aminopropyl)tetramethyldisiloxane (APTMDS), is introduced as a means of improving the mechanical properties of the pristine polyimide (PI) separator through hydrolysis-cross-linking. Moreover, dopamine (DA) undergoes self-polymerization to form polydopamine (PDA), which adheres to the surface of the composite separator. This process enhances the compatibility of the separator with the electrolyte. The three-layer composite separator of PI/APTMDS/PDA displays superior wettability, fire resistance, and conductivity in comparison to those of a Celgard-2400 separator. In particular, PI/APTMDS/PDA separators display superior battery capability (128.17 mAh·g–1@5 C, LiFePO4IILi) in comparison to polypropylene separators (115.4 mAh·g–1@5 C, LiFePO4IILi). Moreover, the cell employing the PI/APTMDS/PDA separator displays high cycling stability and discharge specific capacity over 100 cycles at 1 and 9 C. The present study offers an excellent design concept for the preparation of modified separators for LIBs.
研究领域:
材料科学
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS LETTERS
·
2024
·
IF 2.7
Xiaohua Li,Kunfeng Li,Huilong Shao,Shuang Zhao,Guobing Chen,Zhen Zhang,Zhicong Gan,Yilong Song,Zichun Yang
The freeze-casting is widely utilized as a tool for regulating micro-scale pore structures in the fabrication of flexible polyimide (PI) aerogels for applications in adsorption, filtration, and fire-retardant. Herein, a confinement-controlled freeze-casting method is developed to fabricate PI aerogels with excellent thermal insulation properties by designing multi-scale structural adaptability. In a confinement-controlled system, the enhanced solid/solid and solid/liquid interface interactions in the solution dispersion system induce dendritic evolution of ice crystals. Under the directional freezing, grown dendritic ice crystals squeeze the loaded particles to form polyamic acid salt (PAAs) cryogels. Followed by template removal and thermal imidization, PI aerogels with a micro/nano-scale slit-like porous structure were obtained. The PI aerogels are characterized by ultra-low density (as low as 9.82 mg/cm 3 ) and exceptional thermal insulation performance (25.0 mW/(m·K) at 25 °C).
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
JOURNAL OF POLYMER SCIENCE
·
2025
·
IF 3.6
Muke Zhang,Yafei Yu,Yang Liu,Liang Chen,Qin Chen,Jinchao Li,Yaping Zhang
Recently, colorless polyimide (CPI) substrates with excellent optical properties, a suitable thermal stability, and a low dielectric constant have become a key factor in the development of wearable and portable flexible electronic devices. A series of branched CPI films has been successfully prepared here by using a self-made triamine (1,3,5-triple (2-trifluoromethyl-4-aminobenzyl) benzene [TFAPOB]). By adjusting the ratio of the cyclopentanone bis-spironorbornane tetracarboxylic dianhydride (CPODA) monomer and the 4,4-(hexafluoroisopropyl)-diphthalic anhydride (6FDA) monomer, an optimal film (CBPI-10) with the highest content of CPODA was obtained. This film could achieve the highest transmittance of 90% at 550 nm and the highest glass transition temperature of 311°C. This result could be explained by the fact that CBPI-10 contained the least amount of trifluoromethyl side groups and the largest amount of alicyclic units, which resulted in the generation of the minimum free volume fraction (according to molecular dynamics simulations) and the disruption of the conjugation effect between the benzene rings. Additionally, it is worth mentioning that the highest dielectric constant of these films was only 2.17, which was significantly higher than those of traditional CPI polymers (2.61–2.72). Consequently, the present study has focused on developing a novel manufacturing scheme for branched CPIs, which is of guidance importance for the design of colorless polymers and the advancement of flexible display technology. Graphical
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2025
·
IF 7.9
Haiyan Guo,Lingbin Liu,Yuxiu Yu,Qiang Zhang,Qing Chang,Yaodong Liu
Binders play a vital role in silicon-based anode materials. In this study, we design and synthesize a series of silicon-based anode binders by incorporating functional monomers such as Diaminobenzoic acid (DABA), Aminopropyl terminated polydimethylsiloxane (PDMS) and 4,4′-diphenyl ether dianhydride (ODPA) into polyimide (PI) backbones. The goal is to develop binders with a balance of rigidity and flexibility to improve the electrochemical performance of silicon anodes in lithium-ion batteries. It is found that the chemical structure of the binder affects the swelling rate, bond strength and rigidity, which thereby impacts the electrochemical performances of silicon anode. The incorporation of (PDMS) enhances the binder's flexibility, which effectively accommodates the volume expansion of silicon during cycling, thereby improving cycling stability. However, excessive PDMS content leads to increased swelling rates and weakened adhesion, negatively affecting the formation and stability of the solid electrolyte interphase (SEI) layer and reducing first Coulombic efficiency (ICE). The co-polymerization of 1,3-bis(aminopropyl) tetramethyldisiloxane (NH 2 -DS) reduces the binder's solubility, resulting in improved ICE. Among the binders tested, Si@ODPA-NH 2 -DS-DABA exhibits the best cycling performance, has a specific capacity of 1690.2 mAh g −1 after 200 cycles at 0.2 C, due to its optimal rigid-flexible ratio, lower swelling rate, and stronger adhesion to the electrode. The synergistic effect of rigid benzene rings, imide bonds, and flexible ether and Si-O-Si units provide high strength, toughness, and adhesion. This study provides valuable insights into the design of silicon anode binders, demonstrating that a careful balance of binder flexibility, swelling rate, and adhesive strength is essential for achieving superior electrochemical performance and long-term cycling stability.
研究领域:
材料科学
·
电化学
·
电池技术
✓ 已验证
产品关联
DOI
高影响因子
TRIBOLOGY INTERNATIONAL
·
2024
·
IF 6.1
Jiayuan Yan,Yanming Wang,Fengli Liu,Xiaoliang Zhang,Yongxing Liu,Wangfei Shen,Zhixiao Zhang,Ping Li,Yafeng Wang,Chunxia Wu
At the nanoscale, the surface properties of nanomaterials are of utmost importance. Amino-functionalized MXene (AMXene) was prepared by grafting 3-aminopropyltriethoxysilane (APTES) upon the top layer of Ti 3 C 2 T x . AMXene is introduced into the polyimide (PI) matrix coatings. The findings indicate that the dispersion of AMXene in PI is further substantially enhanced based on the principle of “similar compatibility”, which is attributable to the creation of more hydrogen bonds between AMXene and highly polar PI matrix molecular chains. The addition of AMXene lowered the factor of friction by 34.1 % and the rate of abrasion by 84.8 % compared to unadulterated PI. In addition, the PI/AMXene composites exhibit significant reinforcement properties at different loads and speeds.
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2024
·
IF 6.3
Jialin Zhang,Jie Dong,Xin Zhao,Xiuting Li,Qingsong Xu,Qinghua Zhang
With the trend toward lighter and longer-lasting spacecraft operating in harsh environments, developing advanced high-performance polymer materials with adequate photostability has become an urgent issue. Here, a strategy is proposed to introduce UV-absorbing units as pendent side groups into polyimide (PI) backbone to develop intrinsic PI materials through molecular structure design. Compared with direct incorporation into polymer backbone, this method has a minimal impact on diamine reactivity, enabling the preparation of PI with high molecular weights, and more effectively inhibiting initial UV degradation. The addition of only 5 % of functional monomers for copolymerization can significantly enhance UV resistance while maintaining excellent mechanical and thermal properties. Furthermore, for PI fibers, combining chemical structure with the regulation of the aggregate structure during fiber spinning and heat-drawing process can produce high-performance PI fibers with superior overall properties. Unlike the conventional addition of inorganic nanoparticles or organic UV absorbers, this work aims to establish the relationship between chemical structure, material properties, and UV degradation mechanism. It provides a novel approach from the perspective of molecular structure design for advanced high-performance polymers that require complex processing and stringent performance demands, including long-term UV resistance and mechanical performance.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER COMPOSITES
·
2024
·
IF 4.8
Shiyun Fu,Haihong Ma,Fengmei Ren,Zhengfa Zhou,Liguang Fang,Weibing Xu
Polymer composites with heat resistance, good thermal conductivity, and insulation properties can meet the special needs of electronics and electrical appliances. In this work, graphene oxide (GO) and carbon nanotubes (CNTs) are coated by polydopamine (PDA). 4,4′-diaminodiphenyl ether (ODA), pyromellitic dianhydride (PMDA), and 4,4′-oxydiphthalic anhydride (ODPA) in-situ polymerize to prepare poly(amide acid) (PAA) containing thermally conductive yet insulating fillers (PDA@GO, PDA@CNTs). As the concentration of fillers in PI composites increases, the thermal conductivity rises, but the insulation property decreases. Keeping the filler content constant and varying the ratio of PDA@GO and PDA@CNTs, the thermal conductivity increases and then decreases. When PDA@GO and PDA@CNTs have a mass ratio of 10:1, the significant synergistic effect affects the thermal conductivity. The PI/PG 10 C 1 –25 sample has a thermal conductivity of 1.46 W/(m·K), which is 6.9 times greater than the pure PI. Additionally, the volume resistivity, dielectric permittivity, and dielectric loss (100 kHz) of PI/PG 10 C 1 –25 are 2.8 × 10 13 Ω cm, 5.4 and 0.28, respectively. The heat resistance of PI composites is almost the same as that of pure PI. Given these outstanding attributes, the developed PI composites offer vast applications in many fields. Highlights Synergistic PDA@GO and PDA@CNTs (10:1) optimize thermal conductivity. PI/PG 10 C 1 –25 achieves 6.9 times higher thermal conductivity than pure PI. Volume resistivity of PI/PG 10 C 1 –25 reaches 2.8 × 10 13 Ω·cm. Dielectric permittivity of PI/PG 10 C 1 –25 reaches 5.4 at 100 kHz. Developed PI composites maintain excellent heat resistance.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2023
·Vol. 42
·期 4
·521-531
·
IF 4.3
Liu Cun-Sheng,Hu Jun-Qi,Mao Ting-Ting,Liao Song-Yi,Feng Ru-Ming,Liu Yi-Dong,Min Yong-Gang
Metallic copper is widely used as current collector (CC) for graphite anode of lithium-ion batteries (LIBs) due to its high electrical conductivity and electrochemical stability. However, the large volume density of commercial copper foil (∼8.9 g·cm −3 ) limits the increase of energy density of battery. Here, copper-coated porous polyimide (Cu@PPI) was prepared by vacuum evaporation as collector for the graphite anode. The sandwich structure connects the copper metal on both sides of the collector with excellent electrical conductivity. Compared to commercial Cu foil, Cu@PPI has lighter mass (≤3.9 mg for disc of 12 mm diameter versus 9.9 mg of ∼10 µm Cu foil) and lower volume density (≤3.3 g·cm −3 ). In addition, the porous structure allows of better adhesion of reactive substances and electrochemical properties than pure Cu foils. It is estimated that the energy density of Cu@PPI should be much higher than that of Cu foil. This strategy should be applicable for other current collectors.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）