POLYMER COMPOSITES
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2026
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IF 4.9
Jie Chen,Qingjun Ding,Gai Zhao,Huafeng Li,Lin Yang,Guoqing Wang
Polyimide (PI)-based tribological composites containing carbon fiber (CF), molybdenum disulfide (MoS 2 ), and other solid lubricants have been extensively studied. However, the role of hexagonal boron nitride (h-BN) in regulating interfacial interactions and wear mechanisms in PI/CF/MoS 2 systems remains insufficiently understood. In this study, the effects of h-BN incorporation on the mechanical and tribological behaviors of PI/CF/MoS 2 composites were systematically investigated through experimental characterization combined with molecular dynamics (MD) simulations. The results revealed that h-BN addition improved hardness while reducing tensile strength and ductility due to the enhanced interfacial restriction and increased stress concentration. The tribological performance exhibited a non-monotonic dependence on h-BN content, with the optimal performance achieved at 5 wt.% h-BN. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) analyses suggested that an appropriate h-BN content facilitated the formation of a relatively continuous transfer film, whereas excessive h-BN promoted filler agglomeration and interfacial degradation, leading to accelerated wear. Furthermore, MD simulations suggested that the reduced molecular mobility and fractional free volume at the optimal h-BN content were consistent with enhanced interfacial stability. The combined experimental and simulation results provide qualitative insights into the role of h-BN in regulating filler dispersion, interfacial interactions, and molecular chain dynamics. These findings establish a structure–property relationship for designing high-performance multi-filler PI-based tribological composites. Highlights Hexagonal boron nitride improves the hardness but reduces tensile strength. Friction and wear are minimized at 5 wt.% hexagonal boron nitride loading. Excess hexagonal boron nitride triggers agglomeration and abrasive wear. Molecular dynamics simulations corroborate experimental wear mechanisms.
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RAPID COMMUNICATIONS IN MASS SPECTROMETRY
·
2026
·Vol. 40
·期 12
·e70069
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IF 1.8
Jun Huang,Zhiwei Wen,Shijun Gao,Guangqi Wang,Yihan Tang,Minggao Xu,Chengyuan Liu,Yang Pan
Background Online analysis of complex gas mixtures is often hindered by spectral congestion resulting from extensive fragmentation in traditional electron ionization (EI) sources. Although photoionization (PI) provides clean mass spectra by preserving molecular ion integrity, its comprehensive detection is limited by an inherent ionization selectivity toward species with low ionization energies. Methods To address these challenges, a dual-ionization source quadrupole mass spectrometer (DISQMS) integrating PI and EI was developed. Its design and optimization were guided by a multiphysics ion trajectory simulation method coupling continuum-rarefied flow fields with electric fields. The flow field, spanning from the sampling capillary to the quadrupole mass analyzer chamber, was numerically simulated using a hybrid computational fluid dynamics–direct simulation Monte Carlo (CFD–DSMC) method. Results Guided by the simulation, the key instrumental parameters were systematically optimized, and the reliability of the simulation model was validated experimentally. During the detection of acetone, benzene, and air mixtures, clean organic spectra were obtained in PI mode, whereas comprehensive detection of inorganic gases with high ionization energies (e.g., N 2 and O 2 ) and detailed fragment-ion information were achieved in EI mode. Conclusions A DISQMS was developed and validated, and a multiphysics ion trajectory simulation framework was proposed to numerically optimize the instrument's sensitivity. It was demonstrated that complementary detection of organic and inorganic species is achieved through the dual-mode capability. Specifically, spectral interpretation and molecular structure elucidation are effectively facilitated by combining the detailed fragment-ion information from EI with the clean molecular ion data from PI.
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SEPARATION AND PURIFICATION TECHNOLOGY
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2026
·
IF 9.1
Jianqi Mao,Wanli Qiao,Xinping He,Xiwei Qu,Chunhai Yi
ZIF-90 is in-situ grown in benzimidazole-containing polyimide (DB55) via Zn 2+ anchoring for CO₂ separation. • In-situ growth gives uniform filler dispersion and strong interfacial adhesion via Zn 2+ -benzimidazole coordination. • The in-situ grown membrane shows 2.5-fold higher CO₂ permeability than blended MMMs. The intrinsic permeability-selectivity trade-off and CO₂-induced plasticization, exacerbated under high-feed pressure and elevated operating temperatures, severely restrict the application of polyimide membranes in CO₂ capture processes. In this work, a benzimidazole-containing polyimide (DB55) was employed as an anchoring platform for Zn 2+ ions to carry out the confined in-situ growth of ZIF-90 crystals directly within the polymer chains. The coordination bonds between Zn 2+ and the benzimidazole groups of DB55, as evidenced by FTIR and XRD, effectively suppress polymer chain mobility and filler agglomeration, facilitating rapid gas transport. The optimized ZIF-90/dB55–2 membrane exhibits a CO₂ permeability of 269.57 Barrer with CO₂/N₂ and CO₂/CH₄ selectivities of 42.04 and 40.08, respectively, surpassing the 2008 Robeson upper bound for CO₂/CH₄ separation. Compared with physically blended membranes, the optimized in-situ grown membranes show a clear advantage in permeability (approximately 4.4-fold over pristine DB55) along with improved solvent resistance, while the physically blended membranes exhibit slightly higher selectivity due to the partial conversion of Zn 2+ into ZIF-90 during in-situ growth. Temperature-dependent tests reveal that the incorporation of ZIF-90 reduces the activation energies for CO₂, N₂, and CH₄ permeation, and that the ZIF-90/dB55–2 membrane exhibits a smaller decline in CO₂/CH₄ selectivity with increasing temperature than the pristine DB55 membrane. Pressure-dependent tests up to 3.0 MPa further reveal that the MMMs retain stable performance with a smaller loss in CO₂/CH₄ selectivity (6.9%) than the neat polymer (10.0%), indicating enhanced plasticization resistance. This work offers a promising approach to simultaneously improve permeability, selectivity, and operational stability in polyimide-based membranes via in-situ MOF growth within a suitably designed polymer matrix.
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SEPARATION AND PURIFICATION TECHNOLOGY
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2025
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IF 9
Hang Xu,Lili Jiang,Yan Hu,Jitao Lin,Chao Zhou,Zhijun Zhong,Xiaomin Li,Chuanqiang Yin,Changxin Tang,Lang Zhou
Polyimide (PI) has emerged as a promising material for constructing efficient gas separation membranes due to its excellent stability and gas separation properties. Herein, we report a novel composite membrane structure that utilizes the synergistic effect to achieve efficient H 2 /CO 2 separation by skillfully integrating the advantages of three different functional layers. The support layer consists of a PI fiber membrane loaded with zeolitic imidazolate framework-67 (ZIF-67) using an in-situ growth method, which not only enhances the overall mechanical strength of the membrane, but also provides complex gas transport pathways to improve selectivity. The intermediate layer is made of polydimethylsiloxane (PDMS), which prevents excessive penetration of the selective layer solution into the support layer. The selective layer is a mixed matrix membrane composed of polyetherimide (PEI) as the polymer matrix and zeolitic imidazolate framework-67 (ZIF-67) as the porous filler, which provides critical molecular sieving functionality. Compared to pure polyetherimide (PEI) film, the composite membranes have significantly improved mechanical and gas transport properties, with H 2 permeability of 83.4 Barrer and H 2 /CO 2 selectivity of 5.4. Additionally, the composite membranes exhibit excellent hydrophobicity and thermal stability. Given their outstanding overall performance, the composite membranes developed in this study demonstrate significant potential for CO 2 capture and H 2 recovery applications.
研究领域:
材料科学
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化学工程
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膜技术
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气体分离
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纳米技术
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RSC Advances
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2026
·Vol. 16
·期 8
·7178-7188
·
IF 6.1
Jianghui Liu,Shuya Liu,Lili Zhao,Yujun Luo,Yini Ran,Mohan Tang,Guilin Shi,Yuxin Liu,Jianglan Lin,Maoxian Wang,Zhengnan Li,Zhen Yao,Zhusheng Yang,Hai Fu
This study aims to reduce dependence on copper while enhancing the energy density of lithium-ion batteries. Plastic-based current collectors (PBCCs) offer a promising approach to replace copper, minimize the proportion of inactive material, and ultimately increase the energy density of lithium-ion batteries. A key challenge involved the synergistic optimization of the PBCC's conductive framework and its interfacial surface properties. Herein, a PI-CNT-Cu composite membrane was constructed by depositing copper onto electrospun PI fibers containing CNTs. This hierarchical architecture coupled the intrinsic longitudinal conductivity of the CNT network within the fibers with the transverse conductivity of the continuous copper layer, resulting in a composite membrane with a volumetric conductivity of 5.6 × 103 S cm−1. In the electrochemical performance evaluations, graphite anodes employing PI-CNT-Cu CCs exhibited a capacity retention of 95.29% after 190 cycles at 0.5C. The performance enhancement could be attributed to the markedly rougher surface of the PI-CNT-Cu CC (Sa = 2.668 µm) relative to copper foil (Sa = 0.938 µm). This morphology enhanced the contact area and adhesion with the electrode layer, which was crucial for maintaining the structural integrity of the electrode during long-term cycling. In contrast to copper foil, the PI-CNT-Cu CC, with its fiber-woven structure, exhibited a significantly lower areal density with identical thickness values. The capacity of the anode electrode, was calculated based on the total mass including active materials and CCs. Utilizing PI-17%CNT-Cu exhibited significantly higher discharge capacities of 81.7 mA h g−1 at the same rates compared to the Cu foil at 35.08 mA h g−1.
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APPLIED SURFACE SCIENCE
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2020
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IF 6.182
Lushi Kong,Nanxi Dong,Guofeng Tian,Shengli Qi,Dezhen Wu
Surface-enhanced Raman scattering (SERS) spectroscopy is considered as a highly powerful analytical tool for environmental contaminants monitoring, detection of bio/chemical warfare agents, explosive detection and biological sensing. In this study, silver nanoparticles (Ag NPs) decorated polyimide (PI) nanofabric was successfully prepared as an active flexible substrate for SERS. Without any surface modification and activation, this Ag@PI nanofabric SERS substrate was prepared via an integrated process of electrospinning and ion exchange-in situ reduction. ATR-FTIR, ICP, XRD, SEM, and TGA were used to investigate the influencing factors during preparation. p-Aminothiophenol (p-ATP) was used as the probe molecule to characterize the SERS performance of Ag@PI nanofabric substrate. As a result, this Ag@PI nanofabric exhibits remarkable enhancement effect (EF = 9.0 × 10 3 ), good reproducibility, ultra-low detection limit (10 −14 mol/L), and a good linear relationship between the concentration of p-ATP and intensity of its characteristic peak, making it a desirable candidate as the SERS substrate.
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COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
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IF 4.9
Yina Zhuge,Haipei Ge,Fujuan Liu
The white-browed penguin can survive in extreme environments due to its unique feather structure. The feather shafts of penguins are porous, separated by the membrane-pore-like structure made of keratin fiber membranes. The feather branches are densely arranged around the feather shafts. This unique structure provides inspiration for researchers. In this work, we developed a simple method to construct polyimide/polysulfone amide (PI/PSA) membrane-pore-like structure nanofibers resembling penguin feather shafts and studied the effects of different low-boiling point solvents (tetrahydrofuran (THF), ethyl acetate (EA), and acetone (AC)) on the morphology, tensile properties, and thermal insulation properties of PI/PSA membrane-pore-like structure nanofibers. Comprehensive characterization was also performed using scanning electron microscope, total reflection infrared spectrometer, X-ray diffractometer, universal testing machine, thermal conductivity meter, pore size analyzer, thermal gravimetric analyzer, infrared thermal imaging instruments, and thermocouple testing instruments. The results showed that when the mass ratio of THF to N, N-dimethylacetamide (DMAC) was 20/80, the prepared PI/PSA membrane-pore-like structure nanofibers exhibited excellent thermal insulation properties, with a low thermal conductivity of 0.0436 W·m −1 ·K −1 , a breaking strength of 7.72 ± 2.64 MPa, and a breaking elongation of 8.19 ± 4.07 %. The biomimetic membrane-pore-like structure with excellent thermal insulation properties is expected to be applied in various fields, such as heat-protective clothing and architectural coatings in harsh environments.
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CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Haoyu Ma,Jiaozhu Wu,Chengzhe Gao,Silin He,Pengjian Gong,Qiwu Shi,Zhao Wang,Guangxian Li,Chul B. Park
In the context of the future sixth-generation (6G) communication system, the development of multi-functional materials with ultra-low dielectric permittivity ( D k ) and ultra-low dielectric loss ( D f ) is of paramount importance for the design of terahertz (THz) frequency electromagnetic wave transmission devices. In this work, polyimide- block -polydimethylsiloxane (PI- b -PDMS copolymer, PIC) material with low D k , high flexibility and high supercritical fluid foaming ability was fabricated via copolymerization. Additionally, core–shell SiO 2 @BN nanofillers were synthesized by condensing tetraethyl orthosilicate (TEOS) on hexagonal boron nitride (BN) nanofiller surface. Subsequently, flexible polyimide/SiO 2 @BN foam was fabricated via supercritical N 2 foaming. The resulting PIC/SiO 2 @BN nanocomposites exhibit exceptional flexibility and impressive thermal resistance (thermal decomposition temperature 472.2 °C). Notably, the incorporation of core–shell SiO 2 @BN nanofillers leads to the formation of a molecular interface anchoring structure through hydrogen bonding effect. This structure effectively reduced the mobility of the flexible PIC polymer chains on the SiO 2 @BN nanofiller surfaces. Consequently, the porous PIC/SiO 2 @BN materials show a low shrinkage ratio, low dielectric property ( D k = 1.21, D f = 0.012 at 1 THz), excellent THz transmission rate (91.4 %) and long distance 6G THz signal coverage (125.99 m). Furthermore, porous PIC/SiO 2 @BN materials show superior flame-retardant and thermal infrared stealth properties.
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NEW JOURNAL OF CHEMISTRY
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2024
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IF 2.7
Xiaoguang Jiao,Chao Yang,Kaixuan Ma,Caihong Feng,Qingze Jiao,Yun Zhao
Commercial battery separators (Celgard) have poor wettability, poor heat resistance, and low needle punching strength, and the growth of sodium dendrites can easily pierce the separators, seriously threatening the life and safety of room-temperature sodium-sulfur batteries (RT Na-S). In this work, Polyimide copolymerized with polyether (PI-PEO) membrane was prepared by an electrospinning method. By introducing polyether segments into the polyimide molecular chain and constructing a nanofiber structure, the polarity and fiber structure of the material improved the wettability of the electrolyte, and the toughness of the membrane was improved while ensuring the size stability of the membrane and further resisted the puncture of sodium dendrites. As a result, the battery assembled with the PI-PEO separator exhibits excellent cycle stability. The capacity remains 450 mAh g−1 after 2000 cycles at 3 A g-1. At the same time, the PI-PEO shows a higher ionic conductivity (1.48 mS cm-1), better size stability and electrolyte wettability than Celgard. This work provides a novel and effective method for developing durable room temperature sodium-sulfur batteries.
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POLYMER COMPOSITES
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2025
·
IF 4.7
Liang Yu,Qian Wu,Tao Li,Shuai Yuan,Shuangquan Fang,Jiuxin Zhang
Polyimide (PI) materials are highly valued in tribological applications due to their excellent friction-reduction and wear-resistance properties under extreme conditions. However, their relatively low tensile properties limit their effectiveness as standalone materials, necessitating reinforcement. Poly(p-phenylene benzobisoxazole) (PBO) fibers, known for their superior mechanical and tribological properties, struggle with effective interfacial bonding with PI due to low surface activity. This gap in effective reinforcement strategies is critical for advancing PI applications. Here, we address this challenge by anchoring graphene oxide (GO) nanosheets onto PBO fibers using rare-earth (lanthanum) ions, producing RE-GO-RE-PBO fibers with a multi-scale reinforcement structure. The study involved optimizing the rare-earth solution (RES) concentration and characterizing the fiber surfaces. Our results indicate that an optimal RES concentration of 0.3 wt% achieves uniform and stable GO deposition, significantly enhancing interfacial bonding with the PI matrix. The resulting RE-GO-RE-PBO/PI composite exhibited a 91.74% increase in tensile strength and a 58.44% increase in modulus compared to pure PI, alongside improved wear resistance and a low friction coefficient. These findings present a novel strategy for designing high-performance tribological composites by integrating rare-earth-modified nanomaterials into fiber-reinforced matrices. This approach not only addresses the critical challenge of enhancing interfacial bonding but also provides a theoretical and experimental foundation for advanced applications in aerospace and other high-tech sectors, pushing the boundaries of tribological material performance.
研究领域:
材料科学
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摩擦学
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聚合物复合材料
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纳米材料
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表面工程
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CELL RESEARCH
·
2024
·
IF 28.1
Jian Fenglei,Wang Shen,Tian Rui,Wang Yufen,Li Chuangpeng,Li Yan,Wang Shixuan,Fang Chao,Ma Cong,Rong Yueguang
Autophagosome–lysosome fusion mediated by SNARE complexes is an essential step in autophagy. Two SNAP29-containing SNARE complexes have been extensively studied in starvation-induced bulk autophagy, while the relevant SNARE complexes in other types of autophagy occurring under non-starvation conditions have been overlooked. Here, we found that autophagosome–lysosome fusion in selective autophagy under non-starvation conditions does not require SNAP29-containing SNARE complexes, but requires the STX17-SNAP47-VAMP7/VAMP8 SNARE complex. Further, the STX17-SNAP47-VAMP7/VAMP8 SNARE complex also functions in starvation-induced autophagy. SNAP47 is recruited to autophagosomes following concurrent detection of ATG8s and PI(4,5)P 2 via its Pleckstrin homology domain. By contrast, SNAP29-containing SNAREs are excluded from selective autophagy due to inactivation by O-GlcNAcylation under non-starvation conditions. These findings depict a previously unknown, default SNARE complex responsible for autophagosome–lysosome fusion in both selective and bulk autophagy, which could guide research and therapeutic development in autophagy-related diseases.
研究领域:
细胞生物学
·
分子生物学
·
自噬
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高影响因子
PROGRESS IN ORGANIC COATINGS
·
2026
·
IF 7.9
Yujie Rong,Chuanmei Wang,Chaobo Liang,Jin Huang,Guizhe Zhao,Yaqing Liu,Shaofeng Zhou
Quartz fiber (QF)/polyether ether ketone (PEEK) composites are promising for high-temperature wave-transparent applications. However, their performance is severely limited by weak interfacial bonding and interfacial polarization. In this work, a green and thermally stable polyimide-silica (PI-SiO₂) aqueous sizing coating was developed to tailor the fiber/matrix interphase. The PI component enhances interfacial compatibility with the PEEK matrix through molecular chain entanglement, while silane-modified SiO₂ nanoparticles introduce reactive functional groups and nanoscale roughness, enabling interface anchoring and mechanical interlocking. As a result, a dense and gradient interphase with reduced defects is constructed. At an optimal composition (1 wt% PI and 1.5 wt% SiO₂), the interlaminar shear strength, flexural strength, and impact strength increased by 29.72%, 43.27%, and 67.60%, respectively, along with a 21.36% reduction in wear rate. The thermal decomposition temperature increases by 6.54%, accompanied by a 10.03% increase in char yield at 800 °C. More importantly, the dielectric constant is reduced to ∼3.0 with a dielectric loss below 0.02, resulting in enhanced electromagnetic wave transmission in the 2–18 GHz range. This improvement is attributed to the suppression of Maxwell-Wagner-Sillars polarization and defect-induced scattering due to the engineered interphase. This work demonstrates an environmentally friendly and scalable sizing coating strategy for simultaneously improving the mechanical, thermal, tribological, and electromagnetic properties of high-performance thermoplastic composites, providing new insights into interphase design for multifunctional coatings and advanced structural materials.
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危险品化学品经营许可证（带存储）