COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2019
·
IF 3.131
Shengguo Zhou,Wentao Li,Wenjie Zhao,Chao Liu,Zhiwen Fang,Xiulei Gao
As one of the youngest graphene derivative, fluorinated graphene (FG) with excellent mechanical strength and lubricity was incorporated into polyimide polymer (PI) to strengthen the comprehensive performance of nanocomposite . This article gives a detailed characterization to investigate the tribological behaviors of PI/FG nanocomposite films under different friction conditions including both of dry sliding and seawater lubrication . Firstly, the chloroform-treated FG was proved to be stably dispersed in the PI matrix . Subsequently, mechanical properties, thermal stability and tribological properties of PI/FG nanocomposite films were greatly improved. Finally, analysis of the reasons for the significant improvement in wear resistance from the viewpoint of thermal, mechanical properties and the evolution of friction products. Meanwhile, the transfer of FG from polymer matrix to frictional duality was revealed during tribological testing. The above results suggest the potential application of FG in the field of reinforcing polymer friction properties.
研究领域:
材料科学
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高分子材料
·
表面工程
·
摩擦学
·
纳米复合材料
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2020
·Vol. 31
·期 4
·2887-2894
·
IF 2.22
Liu Yuan,Gu Yi-Jing,Deng Jia-Li,Luo Gui-Yang,Wu Fu-Zhong,Mai Yi,Dai Xin-Yi,Li Jun-Qi
A series of LiFe 1− x Mn x PO 4 /C composites were successfully synthesized through a simple hydrothermal method. The effects of doped Mn on their micro-structures and electrochemical performances were investigated. The XRD results indicate that Mn doping cannot change the olivine lattice type of LiFePO 4 . Appropriate Mn doping can reduce the particle size of LiFePO 4 . The electrochemical performance data show that the electrochemical performances of the composite materials are enhanced at first and then decrease as the doping amount of Mn increases. Both the CV and EIS results illustrate that a small amount of doped Mn will reduce the electrode polarization and electrochemical impedance of the samples and simultaneously improve the electrochemical performance. Among all the samples, the LiFe 0.98 Mn 0.02 PO 4 /C sample has a desirable electrochemical performance, with its specific discharge capacity reaching 156.0 mAh g −1 at a rate of 0.1 C. Even at a high rate of 5 C, it can still reach 110.0 mAh g −1 . All the results indicate that an appropriate amount of doped Mn has an emphatic effect on the electrochemical performance of LiFePO 4 /C.
研究领域:
材料科学
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电化学
·
能源存储
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无机化学
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纳米材料
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固态化学
✓ 已验证
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2016
·Vol. 27
·期 11
·1501-1507
·
IF 1.823
Zhubo Liu,Bing Zhou,A.V. Rogachev,M.A. Yarmolenko
Polytetrafluoroethylene (PTFE) composite coatings doped copper acetate and polyurethane (PU) were prepared on rubber substrate by low-energy electron beam dispersion technique. The effects of dopant and glow discharge treatment on the surface morphology, structure and tribological properties of the coatings were investigated. The results showed that Cu–PTFE composite coatings form uniform surface and dense column structure with spherical aggregations under glow discharge treatment. PU coating shows the large size of protuberance structure but PU–PTFE coating presents spherical structure. Both of the coatings become relative dense and smooth after discharge treatment, and Cu–PU–PTFE composite coatings possess a smoother surface and lower polar component of surface energy. Cu doping weakens the crystallinity and ordering degree of composite coatings, but glow discharge increases the ordering degree and branched structure of C―H groups. Friction experiment indicated that Cu fails to improve the wear resistance of PTFE coatings but glow discharge treatment can do it. Cu–PU–PTFE coatings after discharge treatment have the higher wear resistance and lower coefficient of friction. Copyright © 2016 John Wiley & Sons, Ltd.
研究领域:
材料科学
·
表面工程
·
高分子材料
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摩擦学
·
等离子体物理
·
涂层技术
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Lichun Ma,Nan Li,Guangshun Wu,Guojun Song,Xiaoru Li,Ping Han,Gang Wang,Yudong Huang
A novel amine-based functionalization method was developed to improve the interfacial adhesion between TiO 2 NWs and CFs in supercritical water. The microstructure, morphology and mechanical properties of CFs were investigated. It was found that introducing hexamethylenetetramine (HMTA) dendrimers and branched polyethyleneimine (PEI) on CF could increase significantly the adhesion strength between CF and TiO 2 NWs and their interfacial shear strength with epoxy resin, and the order is CF-PEI-TiO 2 NWs > CF-HMTA-TiO 2 NWs > CF-COOH-TiO 2 NWs > CF-TiO 2 NW. Meanwhile, the reinforcing mechanisms and interfacial failure modes have also been discussed. We believe that these effective methods may provide theoretical foundation for the preparation of high performance composite materials.
研究领域:
材料科学
·
复合材料界面工程
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纳米材料修饰
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高分子基复合材料
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2014
·Vol. 2
·期 19
·6740-6746
·
IF 0
Weining Sun,Xiaofeng Lu,Yan Tong,Junyu Lei,Guangdi Nie,Ce Wang
In this report, a palladium/polypyrrole/polyacrylonitrile (Pd/PPy/PAN) composite nanofiber membranes was synthesized by a one-pot redox polymerization process between pyrrole monomers and Na2PdCl4 in the presence of electrospun PAN nanofibers, without the introduction of any other surfactants or reductants. The as-prepared Pd/PPy/PAN nanofiber membrane exhibited good catalytic performance towards hydrogen generation from the hydrolysis of ammonia borane (AB). The apparent activation energy (Ea) was calculated to be about 33.5 kJ mol−1. In addition, the Pd nanoparticles (Pd NPs) were encapsulated in PPy layers on the surface of the PAN nanofibers, enabling the catalyst to be stable against poisoning and easily separated from the suspension system. The catalytic activity does not weaken after five cycles. This study indicated that the obtained Pd/PPy/PAN composite nanofiber membrane could be applied as an alternative in exploring new catalysts for hydrogen generation, as hydrogen is an important fuel as a clean power source.
研究领域:
材料化学
·
纳米催化
·
能源材料
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高分子科学
·
氢能源
✓ 已验证
DOI
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Rui Huang,Hongye Wang,Cheng Tao,Hua Hao,Zhonghua Yao,Hanxing Liu,Minghe Cao
Thin film capacitors with large energy storage density and high breakdown strength are widely used in modern electronic fields. To solve the problems of interface effect and different polarization mechanism between matrix and fillers in conventional heterogeneous structure composite thin film capacitors, a new-type inorganic microcrystal-amorphous composite film of 0.92BaTiO 3 -0.08Bi(Ni 0.5 Zr 0.5 )O 3 (0.92BT-0.08BNZ) are prepared by sol–gel method. The amorphous matrix improving the breakdown strength is introduced into the film by adjusting preparation technology. Moreover, the nano-scale polar microcrystalline regions (fillers) are introduced and uniformly distributed in the amorphous matrix under various annealing temperatures. Through investigating the influence of different amorphous matrix and microcrystal trend on the dielectric and energy storage properties, it is found that synergistic effect between the polarized microcrystalline regions and the amorphous matrix are optimal at an annealed temperature of 550 ℃. The result shows that a high energy storage density of 103.7 J cm −3 and an efficiency of 88.3% are obtained under the electric field of 8.30MV cm −1 . Simultaneously, the excellent dielectric and energy storage stability is achieved in a wide temperature range of 20–200 °C. Conclusively, this microcrystal-amorphous composite film overcome the low energy storage capability and poor thermal stability of conventional composite films and provide a feasible way for preparing high energy storage performance films.
研究领域:
材料科学
·
介电材料
·
储能技术
·
无机非金属材料
·
功能薄膜
✓ 已验证
DOI
高影响因子
PLANT CELL AND ENVIRONMENT
·
2021
·Vol. 44
·期 11
·3681-3699
·
IF 7.228
Yushan Zhai,Quan Yuan,Shiyou Qiu,Saisai Li,Miaomiao Li,Hongying Zheng,Guanwei Wu,Yuwen Lu,Jiejun Peng,Shaofei Rao,Jianping Chen,Fei Yan
Chloroplasts play crucial roles in plant defence against viral infection. We now report that chloroplast NADH dehydrogenase-like (NDH) complex M subunit gene ( NdhM ) was first up-regulated and then down-regulated in turnip mosaic virus (TuMV)-infected N. benthamiana . NbNdhM -silenced plants were more susceptible to TuMV, whereas overexpression of NbNdhM inhibited TuMV accumulation. Overexpression of NbNdhM significantly induced the clustering of chloroplasts around the nuclei and disturbing this clustering facilitated TuMV infection, suggesting that the clustering mediated by NbNdhM is a defence against TuMV. It was then shown that NbNdhM interacted with TuMV VPg, and that the NdhMs of different plant species interacted with the proteins of different viruses, implying that NdhM may be a common target of viruses. In the presence of TuMV VPg, NbNdhM, which is normally localized in the nucleus, chloroplasts, cell periphery and chloroplast stromules, colocalized with VPg at the nucleus and nucleolus, with significantly increased nuclear accumulation, while NbNdhM-mediated chloroplast clustering was significantly impaired. This study therefore indicates that NbNdhM has a defensive role in TuMV infection probably by inducing the perinuclear clustering of chloroplasts, and that the localization of NbNdhM is altered by its interaction with TuMV VPg in a way that promotes virus infection.
研究领域:
植物病毒学
·
分子植物病理学
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叶绿体生物学
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植物免疫学
·
分子病毒学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·Vol. 48
·期 16
·23258-23265
·
IF 5.532
Jianlong Chai,Yabin Zhu,Xing Gao,Tielong Shen,Lijuan Niu,Shufen Li,Peng Jin,Minghuan Cui,Zhiguang Wang
Al 2 O 3 /SiC ceramic composites with different SiC contents have been prepared by powder metallurgy at 1600 °C for 120 min at 30 MPa pressure. The effect of second phase particles on the microstructure and mechanical properties of composites have been studied. The results show that SiC particle has a significant impact on the matrix subjected to residual stress, and on the microstructure of the composites as well. The average grain size of alumina matrix decreases as the SiC particle content increases. Simultaneously, it has been found that the mechanical properties of the material are significantly enhanced in comparison with monolithic Al 2 O 3 . The highest strength and toughness are obtained when the SiC content is 15 vol%, and the values are 1237 MPa and 5.68 MPa m 1/2 , respectively. The mechanisms of strengthening and toughening have been discussed.
研究领域:
材料科学
·
陶瓷学
·
复合材料工程
·
固态物理
·
粉末冶金
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Pingfan Xu,Yaofa Luo,Peikun Zhang
Polyurethane (PU) composites integrated with outstanding fire retardancy, smoke suppression as well as ameliorated mechanical property is attractive, but remains a challenge. Here, we demonstrate the interfacial architecting of organic–inorganic hybrid (ACAPP) by reacting renewable chitooligosaccharide (COS) with ammonium polyphosphate (APP) and ammonium octamolybdate (AOM) via a one-pot, facile and eco-friendly approach. The ACAPP with multiple hydroxyl groups shows good compatibility and strong interfacial adhesion force with PU matrix due to the abundant covalent cross-linking points and hydrogen bonds networks. The incorporation of 15 wt% ACAPP enables the resultant PU composite to achieve a V-0 rating, a limiting oxygen index of 26.1%, 31.1% and 44.8% reduction in total heat release and total smoke production, respectively, far outdistancing conventional APP. The suppressed fire hazards mainly benefits from the synergy catalytic carbonization effect of ACAPP in condensed phase. Moreover, ACAPP reinforces the tensile strength of PU whilst retaining the decent ultimate elongation. This work may offer a referable exemplification for constructing green flame-retardant to balance high fire safety and mechanical properties.
研究领域:
高分子材料科学
·
阻燃化学
·
复合材料工程
·
绿色化学
·
材料界面科学
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2022
·
IF 9.794
Die Su,Jianping Yang,Qingshui Hong,Min Yang,Jiaxing Wen,Qianfu Wang,Hai Hu,Li Liu,Xiukang Yang
Pseudo-capacitive materials show long cycling life as anode of K-ion battery (KIBs), yet low specific capacity and poor rate performance. Herein, the porous TiNbO 4 /C nanofibers (denoted as TNO/C) are synthesized via electro-spinning. Abundant oxygen vacancies and large specific surface area make the sample exudes high specific capacity and good rate performance. After optimizing the calcination temperature, it is found that the porous TiNbO 4 /C nanofibers at 700 °C (denoted as TNO/C-700) can deliver the specific discharge capacity of 250.4 mAh g −1 in K-ion half cell and demonstrate good cycle stability for 100 cycles in K-ion full cell in 100 mA g − 1 . Even in 5 A g − 1 , the discharge capacity of TNO/C-700 electrodes is still 116.7 mAh g − 1 at rate performance. Ex-situ XRD results show that this TNO/C-700 electrode is associated with pseudo-capacitive effect and insertion/de-insertion process. The TNO/C-700 electrode exhibits a high pseudo-capacitive contribution, which can reach to 85.0% at 3 mV s −1 . This novel high pseudo-capacitive contribution anode material provides more possibilities for the selection in KIBs.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
·
无机非金属材料
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2017
·Vol. 52
·期 19
·11701-11714
·
IF 2.599
Wei Xiuzhen,Hong Jialiang,Zhu Shuangshuang,Chen Jinyuan,Lv Bosheng
Polyethyleneimine (PEI) of various molecular weights and trimesoyl chloride (TMC) were utilized to prepare composite nanofiltration (NF) membranes via interfacial polymerization. The changes in the surface structure and chemical composition of the prepared membranes were evaluated using SEM, ATR-FTIR, XPS and surface potential measurements. The pure-water flux and rejection rates of the inorganic salts (MgCl 2 , MgSO 4 , Na 2 SO 4 and NaCl) through the resultant NF membranes were also investigated. The results showed that the performance of the composite NF membranes was significantly affected by the molecular weight of the PEI. Notably, the permeate flux and rejection rate of the NF membranes increased with the PEI molecular weight. In addition, when the NF membranes were used to treat actual wastewater from the electroplating industry, the NF membranes presented high-efficiency separation properties for heavy metal ions. The rejection rates of the NF membranes at 0.4 MPa for chromium, nickel, zinc and copper ions reached 92.6, 89.6, 89.2 and 86.3%, respectively.
研究领域:
材料科学
·
膜分离技术
·
环境工程
·
高分子化学
·
水处理
✓ 已验证
DOI
高影响因子
Defence Technology
·
2023
·
IF 5.1
Weitao Yang,Yuchen Gao,Rui Hu,Manman Li,Fengqi Zhao,He Jiang,Xuan Zhang
Smart materials, which exhibit shape memory behavior in response to external stimuli, have shown great potential for use in biomedical applications. In this study, an energetic composite was fabricated using a UV-assisted DIW 3D printing technique and a shape memory material (SMP) as the binder. This composite has the ability to reduce the impact of external factors and adjust gun propellant combustion behavior. The composition and 3D printing process were delineated, while the internal structure and shape memory performance of the composite material were studied. The energetic SMP composite exhibits an angle of reversal of 18 s at 70°, with a maximum elongation typically reaching up to 280% of the original length and a recovery length of approximately 105% during ten cycles. Additionally, thermal decomposition and combustion behavior were also demonstrated for the energetic SMP composite.
研究领域:
材料科学
·
高分子化学
·
推进剂技术
·
智能响应材料
·
增材制造
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）