TALANTA
·
2024
·
IF 5.6
Xiaoxia Zhang,Jinchang Liu,Han Zhang,Qinming Zhang,Jiwei Shen,Yinmao Wei,Chaozhan Wang
Efficient enrichment is crucial for the highly sensitive monitoring of phenylurea herbicides (PUHs) in various environmental waters. In this work, a stable core-shell spherically magnetic polyimide covalent organic framework (COF) was synthesized via a simple template-mediated precipitation polymerization method under mild conditions using tri(4-aminophenyl)amine (TAPA) and 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA) as the building units (denoted as Fe 3 O 4 @TAPA-BPDA). The Fe 3 O 4 @TAPA-BPDA exhibits remarkable adsorption performance for PUHs with an optimized adsorption time of only 10 min. The adsorption of PUHs by Fe 3 O 4 @TAPA-BPDA followed the pseudo-second-order kinetic model and the Langmuir model. Furthermore, hydrogen bonding , halogen bonding, hydrophobic interaction, electro donor-acceptor interaction and π-π interactions are identified as the dominant mechanisms contributing to excellent adsorption performance. It was demonstrated that halogen bonds play an important role in the adsorption of substances containing chlorine atoms . The Fe 3 O 4 @TAPA-BPDA is easy to operate and highly regenerable. A simple magnetic solid-phase extraction (MSPE) method based on the Fe 3 O 4 @TAPA-BPDA was then developed for the rapid extraction of five PUHs in real samples, coupled with high-performance liquid chromatography (HPLC) determination. The analytical method developed has a linear range of 0.5–50 ng/mL, and the limit of detection (LOD) ranges from 0.06 to 0.10 ng/mL. The method exhibits good accuracy with recoveries ranged from 74.5 % to 111.4 %. The analytical method was successfully applied to the highly sensitive detection of PUHs in environmental water samples, which highlighting the potential application of the Fe 3 O 4 @TAPA-BPDA in the sample pretreatment.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Xianyu Sun,Shiqin Xu,Yuelin Jin,Tao Cai,Xiaodong Wang,Hongqing Niu,Dezhen Wu
Global demand for lithium (Li) is experiencing a significant growth. A green and effective solution has been devised to address the increasing demand for resource recovery of Li from recycled Li-ion batteries. The objective of this study was to chemically graft 4′-Aminobenzo-15-crown-5-ether (AB15C5) onto polyimide (PI) fiber through a three-step method, resulting in the successful fabrication of AB15C5-functionalized PI fiber (PI-g-AB15C5). The PI-g-AB15C5 fiber exhibits a specific surface area of 2.69 m 2 g −1 as determined by Brunauer-Emmett-Teller analysis. The textiles derived from PI-g-AB15C5 are particularly significant. The textiles exhibit a higher specific surface area and elevated free pore volume, which enhance the full exposure of crown ethers and the adsorption of Li + . The PI-g-AB15C5 fiber exhibits advantageous hydrophilicity, has a significant equilibrium adsorption capacity for Li + (qmax = 21.09 mg g −1 ), demonstrates remarkable repeatability in cycling tests, displays excellent tensile properties, and maintains its fabric morphology during the adsorption process. PI-g-AB15C5 fiber effectively retrieved Li + in an acidic setting. When four interfering ions (Na + , K + , Co 2+ , and Mn 2+ ) were present, the PI-g-AB15C5 fiber demonstrated a remarkable ability to adsorb Li + selectively. The selective separation factors of Li + for Na + , K + , Co 2+ , and Mn 2+ were 8.47, 18.88, 6.99, and 9.85, respectively. A literature survey revealed that PI-g-AB15C5 fiber had better selective separation factors. The selectivity of PI-g-AB15C5 fiber towards Li + is supported by Density Functional Theory (DFT) calculations, which show that the greater Gibbs free energy change of the PI-g-AB15C5–Li + complex (−1008.82 kcal mol −1 ) is responsible for this exceptional selectivity. In summary, the functionality of this study’s polymer fiber material provides an effective method for recovering Li + from recycled Li-ion batteries. It can efficiently adsorb Li + , facilitating their selective separation from other heavy metals.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Linyan Wang,Wenjie Li,Chen Wang,Yuncong Jiang,Hang Liu,Tianliang Pang,Xiaodong He,Mingwei Li,Fei He
The extremely low thermal conductivity, low density, and high-temperature stability of polyimide (PI) aerogels are promising candidates for thermal insulation applications. In this work, the layered PI/Al 2 O 3 composite aerogels (PACAs) were developed, inspired by the biomimetic idea of a “cocktail” layered structure to enhance the service temperature of PI. By exploiting the density difference between the water-soluble polyimide acid (PAA) solution and Al 2 O 3 slurry, we successfully fabricated PACAs with a macro-scale layered structure through side-direction freezing and thermal imidization processes. The PACAs exhibit significant anisotropic structural characteristics, with pore channels presenting a honeycomb structure in the Z-direction, effectively suppressing heat transfer along this direction. Both PI and Al 2 O 3 aerogels demonstrate anisotropic properties in different directions, with the PI aerogel achieving excellent thermal insulation with a thermal conductivity of 0.0197 W/(m·K) along the Z-direction. By adjusting the relative thickness of the PI and Al 2 O 3 layers, optimal thermal insulation performances were achieved at temperatures of 300 °C, 600 °C, and 900 °C. These results showcase the innovative advantages of the layered structure in enhancing thermal insulation while leveraging the low thermal conductivity of PI and the high-temperature tolerance of Al 2 O 3 .
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2025
·
IF 9
Mengchen Wang,Jiayou Liao,Chengyun Gao,Jiwei Ma,Xianjie Meng,Yinghua Shen,Xu Wu,Yong Wang,Jinping Li
Hyperbranched polyimide (HBPI) membranes have emerged as promising materials for gas separation due to their loose interchain structure and large free volume. However, their widespread application is hindered by challenges such as complex synthesis procedures, high-cost monomers, and poor resistance to plasticization. In this study, a series of Trimesoylchloride (TMC)-branched 6FDA-based PI membranes were successfully synthesized using different contents of TMC as a branching agent to regulate the pore distribution. The molecular structure and degree of branching (DB) of HBPI were characterized using FTIR and 1 H NMR. The incorporation of TMC into the HBPI structure effectively enhanced the permeability and selectivity of the acyl chloride-branched PI membranes while improving thermal stability. The optimized membrane (A5-TMC content is 5%), exhibits the improving O 2 and CO 2 permeabilities of 176.52 and 930.94 Barrer combined with the O 2 /N 2 , CO 2 /N 2 and CO 2 /CH 4 selectivities of 4.68, 24.65 and 23.85, respectively. Particularly, the A5 HBPI membrane, with a DB value of 85.71%, demonstrated superior anti-aging properties compared to linear 6FDA-DAM membrane over 365 days. Most importantly, the 6FDA-DAM-TMC HBPI membranes significantly enhanced the resistance to plasticization at elevated CO 2 feed pressures, maintaining stability up to 300 psi and significantly outperforming the linear 6FDA-DAM membrane. This study provides an effective method for the fabrication of high-performance gas-separated polymer membranes with enhanced plasticization resistance and long-term durability for advanced gas separation applications.
✓ 已验证
产品关联
DOI
高影响因子
TRIBOLOGY INTERNATIONAL
·
2025
·
IF 6.9
Chunying Min,Yaxiang Su,Hang Yu,Hongyu Liang
Developing sustainable thermosetting resins and their composite materials is one of the key research topics in the field of sustainable tribology today. This study prepared a series of polyhexahydrotriazine-crosslinked polyimide (PI-PHT) films featuring rigid skeleton-dynamic networks through polycondensation of amine-terminated polyimide oligomers with formaldehyde. The PI-PHT/250 °C film demonstrated outstanding tribological performance in various complex friction environments owing to its highly crosslinked rigid-flexible network, exhibiting a specific wear rate 55 % lower than conventional thermosetting polyimides (TBPI). Crucially, these high-performance films achieve complete degradation and recycling under acidic conditions (pH < 2, 25 °C). PI-PHT films and their composites uniquely combine exceptional wear resistance with recyclability, presenting significant application potential in sustainable tribology.
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2025
·
IF 8.9
Zhengying Tu,Zuoxiang Xie,Qinhua Zhou,Jing He,Yuyang Dong,Chengzhe Huang,Fei Zhang,Qingbin Zheng,Yinhang Zhang
The escalating density of electronic devices underscores the imperative for efficacious thermal management strategies. Graphene (GNPs)-based composite films, renowned for their exceptional thermal conductivity, have emerged as a focal point in addressing the heat dissipation conundrum within integrated circuits. This study introduces an innovative approach to fabricating SiC/graphene/polyimide (PI) composite films, employing a one-step in-situ polymerization process in conjunction with a high-pressure orientation technique. The resultant films are engineered to augment thermal conductivity in both in-plane and through-plane orientations, thereby surmounting the intrinsic shortcomings of traditional graphene-based materials that suffer from suboptimal out-of-plane thermal characteristics. The incorporation of silicon carbide (SiC) particles catalyzes the alignment of graphene within the PI matrix, thereby constructing an efficacious thermal transport network. The composite films exhibit markedly enhanced thermal conductivity (In-plane thermal conductivity is 16.6, and out-of-plane thermal conductivity is 3.11) , electrothermal performance (Under a voltage of 3.9 V, the thin film reaches a high temperature of 338 °C) , and electromagnetic shielding efficacy (35 dB) . In the realm of battery applications, these films facilitate efficient heat dissipation and pre-heating, consequently bolstering battery capacity. Moreover, the utilization of environmentally benign materials and a solvent-free fabrication methodology renders these films ideally suited for electronic device applications that demand robust heat dissipation and unwavering reliability.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Yanshuang Gu,Xiaoran Zhang,Lixue Zhou,Peng Yu,Peng Huang,Daming Feng,Chunhua Ge
The urea oxidation reaction (UOR) plays a crucial role in advancing electrochemical energy storage systems and in the remediation of urea-contaminated wastewater. However, progress in UOR technology has been hindered by the lack of efficient, cost-effective catalysts. Herein, a functional UOR electrocatalyst, NiS@PPI-TAPT, was developed through uniformly embedding nickel sulfide (NiS) clusters within a porous perylene-based polyimide framework (PPI-TAPT). The resulting catalyst exhibits hierarchical porosity and a spherical microstructure, which significantly enhance active site accessibility and surface area. Additionally, the conjugated structure of the polyimide framework enables rapid electron transfer, thereby improving UOR performance compared to its naphthalene-based analogue, NiS@PPI-TANT, which shows an uneven distribution of NiS. In an electrolyte solution of 1 M KOH containing 0.33 M urea, NiS@PPI-TAPT achieves a current density of 10 mA cm⁻² at a low potential of 1.39 V vs . RHE, surpassing conventional water oxidation systems (e.g., oxygen evolution reaction). Notably, at a current density of 100 mA cm −2 , the overpotential for UOR is 209 mV lower than that of the OER. Moreover, the catalyst demonstrates exceptional reaction kinetics (Tafel slope: 55 mV dec⁻¹) and minimal charge-transfer resistance, highlighting its energy-efficient in urea oxidation. This work presents a rational strategy for designing high-performance, low-cost UOR electrocatalysts through the integration of metal sulfides with conductive porous organic frameworks.
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED MATERIALS
·
2025
·
IF 26.8
Shiya Qiao,Haiming Chen,Yuehao Zhao,Zhen Wang,Jingling Yan
Lightweight polymer-based electromagnetic interference (EMI) shielding materials exhibiting good mechanical adaptability and thermal stability are pivotal for next-generation electronics. However, conventional approaches utilized to enhance the EMI shielding efficiency ( SE ) through porous architectures often compromise the structural integrity of the material or its EMI shielding performance under dynamic deformation. Herein, a morphogenetic approach is proposed to precisely coordinate the precursor thermodynamics by tuning the carbon nanotube (CNT) content and precursor concentration in the framework of the freeze-drying method. With this method, polyimide/CNT aerogels with unprecedented triaxial hierarchical architectures (macroscopic core-radiating patterns, microscopic omasum-like folds, and nanoscopic CNT bridges) are obtained. The synergy between these multiscale structures extends the dissipation pathways of electromagnetic waves by inducing multiple reflections, yielding an EMI SE of 71 dB and an ultrahigh specific efficiency (6470 dB cm 2 g −1 ). Remarkably, the C67-5.0 aerogels also exhibit enhanced EMI shielding performance with temperature (5.0% improvement at 350 °C), a negative Poisson's ratio (around −0.28), and structural stability (≈90% height retention after 500 compression cycles). This unique combination of a high EMI SE, outstanding mechanical properties, and excellent structural compressibility opens new avenues for designing adaptive EMI shielding systems for application to aerospace and electronics industries.
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·Vol. 141
·期 30
·e55704
·
IF 2.7
Ke Yang Ni,Zhao Xin Zhang,Ai Ping Zhang,Jun Bian,Xin Kang Li,Cong Wei,Hai Lan Lin,Dai Qiang Chen
Herein, graphene oxide (GO) and its derivative, reduced GO ( r GO) and p -phenylenediamine (PPD) functionalized GO (GO- g -PPD) were first synthesized and selected as dielectric fillers, and then GO/polyimide (PI), r GO/PI, and GO- g -PPD/PI dielectric nanocomposites were fabricated through in situ polymerization-composition strategy. Fourier transform infrared, Ram, and x-ray diffraction analysis confirmed the success synthesis of r GO and GO- g -PPD dielectric fillers. The mechanical properties showed that GO- g -PPD/PI nanocomposites exhibited the highest tensile strength and elasticity modulus. TGA analysis revealed that the enhancement of thermal stability by addition of dielectric fillers. The dielectric constant of 2.5 wt.% GO- g -PPD/PI nanocomposites reached 25.05, which was 8.55 times that of pure PI (2.93). Energy storage performance tests showed that the energy storage density of GO- g -PPD/PI containing 2 wt.% filler reached 0.77 J/cm 3 , which was 71% higher than pure PI. These findings underscore the potential of GO derivative as a cost-effective reinforcement for PI dielectric nanocomposites for high-temperature capacitive energy storage applications.
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2020
·
IF 3.99
Hanjun Wu,Weijun Zhang,Huali Zhang,Yi Pan,Xiaofang Yang,Zhiquan Pan,Xuejun Yu,Dongsheng Wang
In this work, the novel graphitic carbon nitride (g-C 3 N 4 ) and porous polyimide (PI) supported calcined hydrotalcite-like compounds (g-C 3 N 4 @PI@CHTLcs) were synthesized by co-precipitation and hydrothermal synthesis method, and systematically characterized by physical and chemical methods . The composites showed layered structure and a high thermal stability, and performed well in adsorption of tetracycline (TL), 2, 4-dichlorophenol (DP) and glyphosate (GH). The action pH value was ranged from 7 to 9 for TL and GH, and 3–9 for DP, respectively. The adsorption of TL and DP by g-C 3 N 4 @PI@CHTLcs conforms to the pseudo-first-order kinetic model . While for GH, the kinetic data fit well with pseudo-second-order model, indicating chemical adsorption via electrostatic interaction mechanism. Freundlich isothermal could better describe the adsorption process of TL, DP and GH. The maximum adsorption amounts of TL, DP and GH based on Langmuir isotherm model at 298 K were 231.1, 185.05 and 177.34 mg g −1 , respectively. The adsorption processes of TL, DP and GH were all endothermic and spontaneous, and showed excellent repeatability and stability in regeneration experiments. Additionally, the presence of chloride ion and humic acid (HA) showed no obvious effects on the adsorption process of organic contaminants. The diffusion mechanism of TL, DP and GH on the adsorption process was liquid membrane control. The adsorption mechanism might be the ion exchange between the layers of hydrotalcite, and the surface complexation and hydrogen bonding between various groups of PI and organic contaminants. The research showed that g-C 3 N 4 @PI@CHTLcs was effective in treatment of water containing various organic pollutants .
✓ 已验证
DOI
高影响因子
NANOTECHNOLOGY
·
2022
·Vol. 33
·期 40
·405205
·
IF 3.953
Dezhi Wu,Xianshu Cheng,Zhuo Chen,Zhenjin Xu,Minjie Zhu,Yang Zhao,Rui Zhu,Liwei Lin
Flexible force sensors are of great interest in the fields of healthcare, physiological signals, and aircraft smart skin applications because of their compatibility with curved surfaces. However, the simultaneous detection of multidirectional forces remains an engineering challenge, despite the great progress made in recent years. Herein, we present the development of a flexible capacitive force sensor capable of efficiently distinguishing normal and sliding shear forces. A two-layer electrospun polyimide/graphene oxide (PI/GO) nanofiber membrane is used as the dielectric layer, which is sandwiched between one top electrode and four symmetrically distributed bottom electrodes. This composite membrane has an improved dielectric constant, a reduced friction coefficient, and good compressibility, leading to superior performance that includes high sensitivity over a wide operational range with measured results of 3 MPa−1 for 0–242 kPa (0–2.2 N) and 0.92 MPa−1 for 242–550 kPa (2.2–5 N) in the normal direction; and better than 1 N−1 for 0–3 N in the x- and y-axis directions. The system also has a low detection limit of 10 Pa, fast response and recovery times of 39 ms and 13 ms, respectively, a good cyclic stability of 10,000 cycles at a pressure of 176 kPa, and promising potential for use in high-temperature environments (200 °C). Moreover, a prototype 4 × 4 sensor array has been fabricated and successfully used in a robotic system to grasp objects and operate a wireless toy car. As such, the proposed system could offer superior capabilities in simultaneous multidirectional force sensing for applications such as intelligent robots, human–machine interaction, and smart skin.
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS LETTERS
·
2013
·Vol. 102
·期 25
·
IF 3.794
Zhou Yongcun,Bai Yuanyuan,Yu Ke,Kang Yan,Wang Hong
A polymer based composite was prepared by using modified aluminum fibers and aluminum nanoparticles as fillers in polyimide matrix that resulted in the high thermal conductivity and low relative permittivity. It was found that silica coated aluminum fibers with the multilayer coating structures can significantly reduce the relative permittivity (about 19.6 at 1 MHz) of the composite while keeping lower dielectric loss (0.024 at 1 MHz). The thermal conductivity of composites was significantly increased to 15.2 W/m K. This work shows a useful way to choose proper modifier fillers to improve the composite properties for electronic packaging composite materials.
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）