APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Zhenxiang Liu,Qi Deng,Lixia Long,Shiwei Chen,Yiming Lu,Jinyv Zhang,Chaofeng Zhu,Haifeng Zhou,Yong Huang,Yanzhao Yang
Photothermal evaporation technology can effectively separate pure water from seawater or wastewater, but there are various pollutants in the treatment area. The pollutants not only cause a threat to the environment and biological health, but also block the vapor escape channels inside the absorbent body. Based on this background, this study designs and constructs a dual functional absorber for solar water evaporation and photocatalysis. A superhydrophilic polyimide/carbon quantum dots aerogel (H-PI/CQDs) is prepared. CQDs increase visible light absorption of the aerogels and improve visible-light photocatalytic degradation performance effectively. The photocatalytic degradation mechanism under visible light is proposed. Remarkably, H-PI/CQDs can achieve self-floating and provide continuous and stable water supply during water evaporation. Under the illumination of the sun, the rate of water evaporation is up to 1.59 kg m −2 h −1 . This study successfully achieves water evaporation and photocatalytic degradation, providing a promising method to obtain clean water and prevent environmental pollution.
研究领域:
材料科学
·
环境功能材料
·
光催化
·
能源与可持续发展
·
纳米复合材料
·
水处理技术
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2017
·
IF 6.337
Jianfeng Wang,Xiuxiu Jin,Hong Wu,Shaoyun Guo
The poor dispersion of graphene-based materials and the weak interfacial interaction between the nanofillers and polymer matrix greatly limit the reinforcing efficiency of graphene-based nanofillers on polymers. Moreover, the polymers reinforced with graphene usually tend to be brittle. In this paper, hybrid GO/CNT nanostructure was designed and cross-linked through amide bond, which can disperse and embed into the PI matrix commendably, providing strong interfacial interaction between the nanofillers and the PI matrix. Compared with neat PI, the amide bond hybrid GO/CNT (1.1 wt % in total) can endow the PI matrix with a dramatic increment on strength (118%), modulus (94%), fracture toughness (138%) and electrical conductivity (11 orders), due to the effective stress transfer at the interface between PI matrix and nanofillers as well as at the interface between GO and CNT. Furthermore, the over-all performance of the nanocomposites containing chemical amide bond hybrid GO/CNT is superior to those containing hydrogen bond hybrid GO/CNT and π-π stack hybrid GO/CNT, providing us with a framework to study the interfacial interactions (covalent bond, hydrogen bond and π-π stack) in hybrid GO/CNT nanomaterials and their influence on the performance of polymer nanocomposites.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
Materials Today Physics
·
2022
·
IF 11.021
Long Ni,Yinfu Luo,Chen Qiu,Lu Shen,Huawei Zou,Mei Liang,Pengbo Liu,Shengtai Zhou
Mechanically flexible polyimide foams (PIFs) with exceptional high temperature thermal insulation properties were fabricated by microwave-assisted foaming and post thermal imidization process, using polyester ammonium salt (PEAS) precursor powders which consisted of different molecular chain structures as the derivatives. A comparison of foaming behavior, pore morphology, mechanical and thermal insulation properties between PIFs prepared with mono-dianhydride and copolymerized dianhydride structures was systematically studied. Results showed that the optimum foaming temperatures of PEASs was in the range of 85–150 °C, which correlated with the volatilization of solvents such as H 2 O, tetrahydrofuran and methanol. The introduction of copolymerized dianhydride structure altered the chain rigidity and melt viscosity of PEAS, which improved the cellular structure and mechanical flexibility of PIFs. Moreover, the micron-scale cellular structure of PIFs was determined by melt viscosity, chain rigidity, volatile content and foaming temperatures. The PIFs exhibited low apparent densities (25–30 kg/m 3 ), high open cell rate (95–97%) and mechanical flexibility (compression/release recover rate: 96–99%). All PIFs possessed exceptional thermal stability and thermal insulation properties which can be targeted for thermal insulation applications in the fields of aerospace, transportation, and microelectronics among others.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2022
·
IF 9.879
Qiaoran Zhang,Tiantian Xue,Jing Tian,Yi Yang,Wei Fan,Tianxi Liu
Aerogel fibers, which are beneficial for enhancing the thermal response and preventing the leakage of phase-changeable materials (PCMs) during phase change process , are excellent candidates for phase-changeable textiles with excellent thermoregulating performance. Herein, polyimide/boron nitride (PI-BN) composite aerogel fibers with highly porous structure and good mechanical strength have been prepared by freeze-spinning technique, which could be served as the heat conduction path and skeleton for PCMs. Into the pores of the PI-BN aerogel textile was incorporated polyethylene glycol (PEG) by vacuum impregnation to obtain phase-changeable PI-BN/PEG textile. The high thermal conductivity of PI-BN skeleton could endow the quick thermal response rate of PI-BN/PEG textile upon the phase change process, while the high porosity of aerogel fiber could allow high loading of PEG and inhibit liquid leakage during phase change process. The resultant PI-BN/PEG composite textile has high thermal conductivity (5.34 W m −1 K −1 ), high enthalpy (125.2 J g −1 ) and excellent work stability after 100 heating-cooling cycles, accounting for the desired thermoregulating performance. Moreover, polydimethylsiloxane (PDMS) has been coated on the surface of PI-BN/PEG textile, endowing the textile hydrophobicity , waterproofness and washability, indicating its great potential as candidate for personal thermal management.
研究领域:
材料科学
·
纺织工程
·
热能工程
✓ 已验证
DOI
高影响因子
HIGH PERFORMANCE POLYMERS
·
2018
·
IF 1.047
Yanhua Yang,Pan Jin,Jinzhang Liu,Shijin Ding,Lin Chen,Yueying Chu,Yingzhong Shen
The polyimide (TPA-Cz PI) was synthesized by the reaction of 9-(4′-(4′-diphenylamino)phenylbenzyl)-3,6-diaminocarbazole with 2,2′,3,3′-biphenyltetracarboxylic dianhydride through a classical two-step polymerization process. It exhibited excellent organo-solubility and self-extinguishing property. The synthesized TPA-Cz PI shown excellent film formation. The TPA-Cz PI film sandwiched between an indium tin oxide bottom electrode and Al top electrode. And the fabricated memory device exhibited ternary rewritable storage property in the bias with good data retention and the current ratio of 104:102:1 for ON2, ON1, and OFF states. Its current conduction mechanism by the I-V curves of different conduction models based on the experimental data was analyzed and used to illuminate the physical nature of resistance switching effects. The experimental result indicates that field-induced conformational ordering of the TPA-Cz PI chains and charge-transfer interaction between electron-donor and electron-withdrawing are responsible for the switching behavior. This work can provide a sketch for the design and selection of ternary state resistance random access memory materials in future research.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Chengyang Wang,Shengqi Ma,Dandan Li,Junyu Zhao,Hongwei Zhou,Dezhi Wang,Dongpeng Zhou,Tenghai Gan,Daming Wang,Changwei Liu,Chunyan Qu,Chunhai Chen
Lightweight structures are often used for applications requiring higher strength-to-weight ratios and lower densities, such as in aircraft, vehicles, and various engine components. Three-dimensional (3D) printing technology has been widely used for lightweight polymer structures because of the superior flexibility, personalized design, and ease of operation offered by it. However, synthesis of lightweight polymeric structures that possess both high specific strength and glass transfer temperature (Tg) remains an elusive goal, because 3D printed polymers with these properties are still very few in the market. For example, 3,3′,4,4‘-biphenyl tetracarboxylic dianhydride (BPDA) and p-phenylenediamine (PDA)-type (UPILEX-S type) polyimides show exceptional thermal stability (Tg up to ≈400 °C) and mechanical properties (tensile strength exceeding 500 MPa) and are the first choice if extremely high temperatures of 400 °C or even higher (depending on the duration) are required, which hampers their processing using existing 3D printing techniques. However, their processing using existing 3D printing techniques is hampered due to their thermal resistance. Herein, a 3D printing approach was demonstrated for generating complex lightweight BPDA-PDA polyimide geometries with unprecedented specific strength and thermal resistance. The simple aqueous polymerization reaction of BPDA with water-soluble PDA and triethylamine (TEA) afforded the poly(amic acid) ammonium salt (PAAS) hydrogels. These PAAS solutions showed clear shear thinning and thermo-reversibility, along with high G′ gel-state moduli, which ensured self-supporting features and shape fidelity in the gel state. Postprinting thermal treatment transformed the PAAS precursor to BPDA–PDA polyimide (UPILEX-S type). The resulting layer-by-layer deposition onto lightweight polyimide honeycombs in the form of triangular, square, and hexagonal structures showed tailorable mechanical strength, exceptional compressive strength-to-weight ratio (highest up to 0.127 MPa (kg m–3)−1), and remarkable thermoresistance (Tg approximately 380 °C). These high-performance 3D printed polyimide honeycombs and unique synthetic techniques with general structures are potentially useful in fields ranging from automotive to aerospace technologies.
研究领域:
材料科学
·
航空航天工程
·
化学工程
✓ 已验证
DOI
高影响因子
HIGH PERFORMANCE POLYMERS
·
2015
·
IF 1.286
Weichen Sheng,Qiao Chen,Peijuan Yang,Caifeng Chen
In this article, polyimide (PI) composite films reinforced by graphitic carbon nitride (g-C3N4) have been synthesized using the in situ polymerization process via thermal imidization. Poly (amic acid) (PAA) solutions were prepared from pyromellitic dianhydride (PMDA) and 4,4′-(4,4′-isopropylidenediphenyl-1,1′-diyldioxy) dianiline (BAPP) in N,N-dimethylacetamide (DMAc) solvent. The different amounts of g-C3N4 obtained from the direct pyrolysis of dicyandiamide (DCDA) at 600°C were incorporated into PAA matrix, which formed g-C3N4/PI composite films by thermal imidization. The morphological structures of the synthesized g-C3N4 and g-C3N4/PI composite films were characterized using fourier transform infrared spectroscopy, x-ray diffraction, scanning electron microscopy and transmission electron microscopy. With 2 wt% g-C3N4 incorporated, the tensile strength and elongation at break of g-C3N4/PI composites were increased by about 23% and 21%, respectively, due to the strong interaction between the g-C3N4 particles and PI. Thermogravimetric analysis indicated that the incorporation of g-C3N4 improved the thermal stability of the PI at low g-C3N4 content. Besides, the dielectric and optical properties of these composites were also studied in this article.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
·
2021
·
IF 9.078
Gang Jian,Yong Jiao,Qingzhen Meng,Fei Xue,Liang Feng,Ning Yang,Jianhua Jiang,Minfeng Lü
High temperature (HT) dielectrics have drawn increasing attentions due to strong potentials in capacitors working in extreme temperature conditions. The selection of high temperature ceramic fillers and polymers and the design of composite configurations are crucial for obtaining excellent dielectric and energy storage performances. In this study, PbTiO 3 nanofibers with a confined tetragonality with a lower c/a ratio are synthesized by the molten-salt method and polyimide (PI)/PbTiO 3 nanofiber composites are prepared via the in-situ polymerization. The composite (50 vol% filler loading) possesses greatly enhanced dielectric constant of 46 and low tanδ of ~0.02 at 1 kHz; ε r is 13.9 times larger than 3.3 for PI. From electric displacement-electric field loop investigations, superior energy storage performances of a large discharged energy-density of 16 J cm −3 under 300 MV m −1 and a large charge/discharge efficiency of 80 % are obtained. Furthermore, dielectric constant, energy density and efficiency of the composite exhibit a very good thermal stability from the room-temperature to over 200 °C. Overall, superior properties as well as good thermal stabilities of the PI/PbTiO 3 nanofiber composites indicate strong potentials in HT electrical energy storage capacitors.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
Polymers
·
2022
·Vol. 14
·期 21
·4604
·
IF 4.967
Zhiqing Wu,Fan Lei,Zhiqiang Zhan,Jiangshan Luo,Gao Niu,Zhaoguo Li,Tao Yi,Shufan Chen,Bo Yang,Qiubo Fu,Zhiming Zhang
The exploding foil initiator (EFI) system has been extensively used in ignition and detonation sequences and proved to be of high safety and reliability. Polyimide is considered the ideal flyer material for EFI due to its excellent performance, including thermal stability, outstanding mechanical properties, high radiation resistance, and excellent dielectric properties. In this study, we prepared the EFI based on a polyimide (ODPA-ODA) flyer, which is spin-coated and solidified on patterned copper film in situ. The electric explosion test shows that the prepared EFI has good working performance, and the 4000 V working voltage drove the flyer to reach a maximum velocity of 5096 m/s. The polyimide morphology and chemical structure after the electric explosion was observed by microscope, SEM, XPS, and FTIR, which showed that the polyimide flyer underwent thermal deformation and complex chemical reactions during an electric explosion. A large number of polyimide bonds broke to form new carbonyl compounds, and the opening of aromatic rings was accompanied by the formation of aliphatic hydrocarbon chains. The morphology and chemical structure analysis after the electric explosion test will lay a foundation for us to further understand the working principle and evolution process of polyimide (ODPA-ODA) flyer.Keywords:exploding foil initiator;polyimide;flyer;plasma;morphology;chemical structure
研究领域:
材料科学
·
爆炸物理
✓ 已验证
DOI
PubMed
高影响因子
ACS ES&T Water
·
2021
·
IF 0
Wenzhong Ma,Xinlei Dai,Pei Qiu,Hanwen Ye,Jing Zhong,Hideto Matsuyama
The performance of a cross-linked polyimide (PI) nanofiltration membrane was assessed by interfacial polymerization (IP) combined with the chemical imidization method. With the IP process with m-phenylenediamine and pyromellitic chloride monomers, trimesoyl chloride (TMC) for cross-linking, and the subsequent chemical imidization process, a PI thin film composite (TFC) nanofiltration (NF) membrane was prepared. The results showed that the PI TFC membrane had a high flux of ∼9.13 L m–2 h–1 bar–1 at 4 bar. The effects of the amount of cross-linking agent and reaction time on the NF membranes’ nanofiltration performance were systematically investigated. We selected a CaSO4 salt solution to evaluate the performance of the nanofiltration membrane because the PI TFC nanofiltration membrane’s molecular weight cutoff was in the range of 600–800 Da. The PI membrane rejection to CaSO4 aqueous solution under the optimal preparation conditions reached 93%. When the FCF/water, FCF/DMF, and FCF/ethanol solutions were filtered, the TMC cross-linked PI TFC membrane exhibited a <8% solvent permeation decline but FCF rejection remained at 98%. The PI TFC membrane maintained permeability and salt rejection during the 120 h filtration.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
JOURNAL OF APPLIED POLYMER SCIENCE
·
2025
·
IF 2.8
Jun He,Xiaojing Zhang,Chuyun Cheng,Shuwen Guo,Lu Wang,Weimin Kang,Jun Chen,Jing Yan
Thermal insulation materials are essential for preserving human warmth in cold climates, and biomimetic strategies inspired by natural structures offer powerful design principles. Motivated by the feather architecture of penguins, which endure year-round temperatures of approximately −40°C to −60°C, a high-performance thermal-insulation (HPTI) material that reproduces the key features of feather structure by balancing thermal resistance, ultralow mass, and mechanical flexibility is reported. The HPTI is fabricated via a two-step electrospinning process with tailored spinning parameters to produce a hierarchical, feather-like architecture: a fluffy, air-holding polyimide (PI) nanofiber aerogel paired with a compact PI nanofiber windproof membrane, yielding an ultralow bulk density of 4.15 mg/cm 3 . Surface hydrophobicity is excellent, with water contact angles of 147° (aerogel) and 130° (windproof membrane). The assembled material with an areal density of 190 g/m 2 achieves a thermal-insulation ratio of 97.81%, a clothing insulation (clo) value of 6.518, and a heat-transfer coefficient of 0.72 W/K·m 2 . Combined with favorable compressibility and mechanical compliance, these characteristics make the HPTI a promising candidate for lightweight, flexible garments and protective systems intended for extreme-cold applications, while offering a scalable route to bioinspired thermal-management materials.
研究领域:
材料科学
·
仿生学
·
热工工程
·
纳米技术
·
纺织工程
✓ 已验证
产品关联
DOI
高影响因子
NANOTECHNOLOGY
·
2024
·Vol. 35
·期 47
·475706
·
IF 2.9
Wenrui Li,Xiong Yang,Changchun Qi,Yucheng Zhang,Yibo Dong,Xin Zhao,Zhiliang Gao,Na Feng,Baipeng Song,Guan-Jun Zhang
The exploration of deep space significantly increases the probability of spacecraft failures due to surface electrostatic discharge, which imposes higher vacuum insulation protection requirements on polyimide (PI), the external insulation material of spacecrafts. To address this challenge, this study proposes using silane coupling agent KH550 for organic grafting treatment of Cr2O3 nanoparticles, which are then used to dope and modify PI to enhance the vacuum surface insulation of PI films. The KH550 grafting improves the interface strength between the fillers and the matrix, allowing the fillers to be uniformly dispersed in the matrix. Compared to pure PI films, the prepared PI-Cr2O3@KH550 composite films exhibit significantly enhanced vacuum surface flashover voltage, improved surface/volume resistivity, and dielectric properties. The results demonstrate that PI composite films with 0.8% by mass of Cr2O3@KH550 show the most notable performance improvement, with the DC flashover voltage and impulse flashover voltage in vacuum increasing by 20.7% and 27.8%, respectively. The doping of chromium oxide nanoparticles introduces more deep traps into the PI films and reduce the surface resistivity. The higher deep trap density inhibits charge migration, thereby alleviating secondary electron emission and surface electric field distortion. Simultaneously, the lower surface resistivity facilitates dissipating surface charges and improves the surface insulation. These findings are of significant reference value for promoting the enhancement of aerospace insulation performance.
研究领域:
材料科学
·
航天工程
·
电气工程
✓ 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）