JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
·
2023
·Vol. 33
·期 11
·5667-5681
·
IF 2.3
Dong Shengkang,Guo Zhiwei,Zang Hongshuang,Yuan Chengqing
Polytetrafluoroethylene (PTFE) has great potential for applications in water-lubricated bearings; however, in heavy load conditions at low speeds, PTFE suffers from severe friction and abrasion because of its poor wear resistance. In this study, silicon carbide (SiC) content and particle size are investigated in relation to PTFE water-lubricated composites' tribological properties. The results show that the wear resistance of PTFE composites can be significantly improved when the filling amount of SiC particles was between 3 and 5 wt.%, and the composites containing 5 wt.% SiC reduced wear loss by 99.44%. The composites' friction and wear properties decreased as SiC particle size increased, and wear mechanism for the composites shifted from adhesive to abrasive. Wear loss on PTFE composites filled with 40 nm SiC particles was reduced by 97.03%, showing the best wear resistance. This study provides an experimental basis for the development of high-performance PTFE water-lubricated bearings.
研究领域:
材料科学
·
机械工程
·
摩擦学
✓ 已验证
DOI
高影响因子
TRIBOLOGY LETTERS
·
2019
·Vol. 67
·期 1
·1-17
·
IF 2.235
Zhao Yuanliang,Qi Xiaowen,Zhang Wenli,Fan Bingli,Yang Qingxiang
The effects of copper nanoparticles (Cu) located in different regions of polytetrafluoroethylene/polyimide (PTFE/PI) blends on the morphology, thermal, mechanical, and tribological properties of PTFE composites were studied. Region one is PI phases (the corresponding composites is denoted as PPC), region two is PTFE phases and the interface between PTFE and PI (the corresponding composites is denoted as PPC-m). Results indicate that the incorporation of Cu nanoparticles into PI phases improves the dispersibility and homogeneity of PI phases. As a consequence, the crystallinity of PTFE composites is reduced, but compressive strength and modulus of PTFE composites are enhanced by 50.3% and 14.4% respectively. In addition, self-lubricity and wear resistance of PTFE composites are improved by 10.4% and 50.5%. Scanning electron microscopy (SEM) demonstrates that PI phases with Cu nanoparticles hinder the direct contact between PTFE matrix and counterparts. However, Cu nanoparticles located in PTFE matrix and the interface between PTFE and PI deteriorates the dispersibility and homogeneity of PI phases, which lead to the poor mechanical and tribological performance of PTFE composites.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 52
·47096-47100
·
IF 3.289
Kejun Lin,Duyang Zang,Xiaoguang Li,Xingguo Geng
We study the preparation of superhydrophobic polytetrafluoroethylene (PTFE) coating by a spraying method with copper mesh and aluminum plate substrates. The hydrophobicity and toughness of the resulting surfaces are investigated using water contact angles, sliding angles, rubbing tests, and impact experiments. The heat treatment is found to be the key to adjusting the microstructure as well as the wettability. Sufficient heat accumulation at 230 °C through 50 min sintering gives rise to a hierarchical structure characterised by micro spheres with lots of nanopores on their surfaces, leading to excellent water repellence proved by the large contact angle, and small sliding angle, and the complete water drop rebounce. Insufficient heat accumulation with less than 20 min sintering at 230 °C results in micro spheres without nanopores; the resulting surface presents weak water repellence in all the property tests. In addition, the porous substrate of copper mesh is proved feasible for the spraying preparation of a tough superhydrophobic surface, although it is not as good as the continuous substrate of aluminum plates.
研究领域:
材料科学
·
表面工程
·
高分子材料
·
纳米科技
·
物理化学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2018
·
IF 3.024
Hongyan Tang,Liting Hao,Junchao Chen,Feng Wang,Huapeng Zhang,Yuhai Guo
A facile approach for fabrication of superhydrophobic and superoleophilic alumina membranes through surface modification is presented in this work. The modified alumina membranes were prepared through thermal decomposition of polytetrafluoroethylene (PTFE) materials on the surface of alumina membranes. Contact angle (CA) measurement shows that the modified alumina membranes exhibit superhydrophobicity (155°) and superoleophilicity (0°). Results of Fourier transform infrared spectroscopy, X-ray energy dispersive spectrometry, and X-ray photoelectron spectroscopy indicate that the fluoric groups were formed on the surface of the modified alumina membranes, which may be due to partial decomposition of the PTFE polymer and deposition during the sintering process. This is the key to hydrophobicity. Field emission scanning electron microscopy images demonstrate the occurrence of the fluoric layer, which further indicated that the pore size of the modified alumina membranes decreased. After sintering at 400 °C over 7 h under a nitrogen atmosphere, values of water rejection of the modified alumina membranes for oil/water separation are all higher than 97% over 4 h. A slight reduction in permeation flux can be found over 48 h. The results indicate the fluoric layer is firmly linked with the alumina membranes. The as-prepared membranes may have great potential for oil/water separation.
研究领域:
材料科学
·
膜技术
·
表面化学
·
环境工程
·
分离科学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 17
·52018
·
IF 3.125
Xianggui Zhang,Xianglong Li,Antuo Wang,Bin Yang,Teng Hou,Yishen Lu,Jing Zhou
The separation of stable oil/water emulsions is an urgent global issue. In this work, a porous and superhydrophobic polytetrafluoroethylene (PTFE) fibrous membrane was obtained by first centrifugal spinning PTFE/potato starch fibers and then heat treating the fibers to remove the starch. Results showed that spherical protrusions and irregular striped protrusions appeared on the surface of the prepared PTFE fibers, which significantly increased the roughness and hydrophobicity of the fibrous membrane. In addition, number density and shapes of these protrusions could be tuned by changing the extent of the heat treatment and the potato amylose content during the fiber preparation. The water contact angle on the structured PTFE membranes was as high as 160°, and the water sliding angle was as low as 3.4°. The results of oil/water separation experiments showed that the oil removal rate reached 99.5% based a permeability of 3670 L/m 2 /h, which suggested that the obtained PTFE fibrous membrane has great potential for use in oil/water emulsions separation.
研究领域:
材料科学
·
环境工程
·
膜分离技术
·
表面科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2021
·
IF 9.127
Shigen Bai,Yong Tang,Gong Chen,Yaopeng Wu,Yifu Liang,Shu Yang,Huilong Liu,Yingxi Xie
Supercapacitors (SCs) have garnered increasing attention as an alternative energy storage device but the relatively low potential window and energy density impede their application prospect. Herein, we propose a novel three-dimensional (3D) packaging method for the first time, utilizing high flexible phosphor-copper sheets (PCSs) sprayed with polytetrafluoroethylene (PTFE) and covered with polyimide (PI) films on their both sides as the serial medium followed by CO 2 laser irradiation to fabricate all-solid-state flexible high voltage supercapacitors (HVSCs). This method achieves double voltage output in the limited PI membrane compared with common 2D encapsulation. As a result, as-obtained HVSCs deliver not only an enhanced mechanical tensile strength up to 18.23 MPa but also the outstanding electrochemical performances, including ultrahigh working voltage window (10 V), high energy density (37.68 μWh/cm 2 ) and power density (3.38 mW/cm 2 ). Owing to the excellent flexibility, the HVSCs can be arbitrarily bent or twisted without obvious attenuation on capacitive property. After 10000 cycles, the capacitance retention of HVSCs still maintains to be 90.2%. This novel 3D packaging strategy may pave the way for developing high-performing SCs with wide operating voltage and high energy density for flexible displays, wearable equipment and integrated electrical devices.
研究领域:
材料科学
·
纳米技术
·
能源存储
·
柔性电子
·
电化学
·
高分子材料
·
先进制造
✓ 已验证
DOI
高影响因子
Journal of Tissue Engineering and Regenerative Medicine
·
2022
·Vol. 16
·期 12
·1163-1172
·
IF 4.323
Yulu Liu,Ya Liu,Zhiyuan Bai,Dongfang Wang,Yiyang Xu,Qian Li
With the prevalence of cardiovascular diseases, developing cardiovascular supplements is becoming increasingly urgent. The ability of cells to rapidly adhere and proliferate to achieve endothelialization is extremely important for vascular grafts. In this work, we electrospun polytetrafluoroethylene (PTFE) nanofibrous membranes and used induced crystallization to manufacture poly(ε-caprolactone) (PCL) shish-kebab microstructures on PTFE nanofibers to overcome the inertness of PTFE, and promote cell adhesion and proliferation. PCL lamella periodically grew on the surface of PTFE nanofibers yielding a hierarchical structure, which improved the biocompatibility and mechanical properties of the PTFE nanofibrous membrane. The deposition of PCL lamella improved the hydrophilicity of electrospun PTFE nanofibers membrane, leading to good cell proliferation and adhesion. Also, due to the surface inertness of the substrate material PTFE, this PTFE/PCL composite film has good anti-platelet adhesion properties. Furthermore, cell proliferation could be regulated by controlling the integrity of the PCL crystal network. The vascular patch showed similar mechanical properties to natural blood vessels, providing a new strategy for vascular tissue engineering.
研究领域:
生物医学工程
·
组织工程
·
材料科学
·
心血管病学
·
再生医学
·
生物材料
·
纳米技术
✓ 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
·
摩擦学
·
等离子体物理
·
涂层技术
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2017
·Vol. 53
·期 7
·5204-5215
·
IF 2.599
Teng Xiangguo,Yu Cong,Wu Xiufen,Dong Yichao,Gao Peng,Hu Huili,Zhu Yongming,Dai Jicui
How to solve the crossover of vanadium ions through ion exchange membrane is a key issue in vanadium redox flow battery (VRB), especially for ultra-thin membranes used for VRB to obtain a lower cell resistance. Herein, an ultra-thin (~ 30 μm) PTFE/SPEEK [polytetrafluoroethylene/sulfonated poly(ether ether ketone), P/S] membrane is successfully prepared and modified by using layer-by-layer (LBL) self-assembly technique with polycation poly(diallyldimethylammonium chloride) (PDDA) and polyanion poly(sodium styrene sulfonate) (PSS). P/S membranes are alternatively immersed in positively and negatively charged polyelectrolyte to form 2 to 8 bilayers onto its surface. Consequently, a series of P/S-[PDDA/PSS]
n
( n is the number of multilayers) membranes are fabricated. Both the physicochemical properties and VRB performances of the P/S-[PDDA/PSS]
n
membranes are then investigated in detail. Results show that the ion selectivity of the P/S-[PDDA/PSS]
n
membranes is much higher than that of pristine P/S membrane, especially for P/S-[PDDA/PSS] 6 membrane. As a result, the VRB with the P/S-[PDDA/PSS] 6 membrane exhibits the highest coulombic efficiency (CE) of 96.5% at 80 mA cm −2 , the highest voltage efficiency of 94.7% at 40 mA cm −2 and the highest energy efficiency of 87.7% at both 40 and 50 mA cm −2 , respectively. In addition, 80 times charge–discharge test proves that the P/S-[PDDA/PSS] 6 membrane possesses high stability and no obvious CE decay after running. All the results show that the LBL technique is an effective way to prepare ultra-thin membrane with high ion selectivity for VRB application.
研究领域:
电化学
·
能源材料
·
膜科学
·
储能技术
·
高分子材料
·
电化学工程
✓ 已验证
DOI
高影响因子
FIBERS AND POLYMERS
·
2023
·Vol. 24
·期 12
·4169-4179
·
IF 2.5
Zhang Tingting,Li Zihui,Liu Ya,Ding Kangjia,Guo Yangfeng,Xu Yiyang,Sun Mengfan,Wang Dongfang,Li Qian
Polytetrafluoroethylene (PTFE) nano-porous membrane has been widely used in various fields due to its excellent thermal stability and chemical stability. However, PTFE nanofiber membranes with simultaneous hydrophobic and oleophobic properties are essential to promote the application of PTFE. Here, based on inorganic/organic nanohybridization, we report a strategy for constructing nanostructures on fibers by adding nanoparticles, such as MOF and ZrO 2 . The results of FTIR and XRD confirmed MOF was synthesized successfully. At the same time, the SEM results showed UiO-66-(COOH) 2 is spherical with an average diameter of 152 nm, and there is no agglomeration, which is suitable for electrospinning. Further, MOF and ZrO 2 were payload into PTFE nanofibers. The results of SEM and AFM confirmed nanostructures will be more uniform and pronounced with the increase of UiO-66-(COOH) 2 content, and nanostructures are most obvious when the content of UiO-66-(COOH) 2 is 15%. The introduced nanostructures can increase the oil contact angle of the PTFE nano-porous membrane to 110° without introducing other groups, and further improve the water contact angle from 133° to 145°. Meanwhile, the introduction of a certain amount of hydrophilia groups can increase the oil contact angle to more than 120°. The simple strategy is of great significance to expand the application of PTFE fiber membrane in dealing with waste water treatment fields. Graphical abstract
研究领域:
材料科学
·
纳米科技
·
高分子化学
·
表面工程
·
环境功能材料
·
膜科学与技术
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2013
·
IF 4.093
Qiang Xu,Yang Yang,Jie Yang,Xiaozu Wang,Zhaohui Wang,Yong Wang
Conformal and smooth TiO 2 thin layers were coated on the surface of porous PTFE membranes subjected to a plasma activation process by atomic layer deposition (ALD). In contrast, TiO 2 was deposited on the PTFE surface as globular particulates without plasma activation due to the inert chemical nature of PTFE surface. X-ray photoelectron spectrometry confirmed the formation of functional groups on the plasma-activated PTFE surface which served as active sites for the homogeneous adsorption and reaction of ALD precursors. Scanning and transmission electron microscopy revealed the uniformity of the deposited layer and the precise control of its thickness by changing ALD cycle numbers. The water contact angle measurement showed that the hydrophobic surface gradually turned to be near superhydrophilic with the increment of ALD numbers. Also, the membrane mean pore size was progressively reduced by simply altering the ALD numbers. At proper deposition conditions , the modified membranes gained an increase of pure water flux of more than 150% and simultaneously a doubled retention compared to the original unmodified membrane. This research provides an efficient approach devoid of any harsh treatments to modifying PTFE membranes for achieving specific functions, which also can be applied to other organic materials especially with chemical inert surface.
研究领域:
材料科学
·
膜科学与技术
·
表面工程
·
高分子化学
·
环境工程
·
纳米科技
✓ 已验证
DOI
高影响因子
Nanoscale Research Letters
·
2019
·Vol. 14
·期 1
·1-9
·
IF 3.159
Lin Shizhe,Cheng Yongliang,Mo Xiwei,Chen Shuwen,Xu Zisheng,Zhou Bingpu,Zhou He,Hu Bin,Zhou Jun
Polytetrafluoroethylene (PTFE) is a fascinating electret material widely used for energy harvesting and sensing, and an enhancement in the performance could be expected by reducing its size into nanoscale because of a higher surface charge density attained. Hence, the present study demonstrates the use of nanofibrous PTFE for high-performance self-powered wearable sensors. The nanofibrous PTFE is fabricated by electrospinning with a suspension of PTFE particles in dilute polyethylene oxide (PEO) aqueous solution, followed by a thermal treatment at 350 °C to remove the PEO component from the electrospun PTFE-PEO nanofibers. The obtained PTFE nanofibrous membrane exhibits good air permeability with pressure drop comparable to face masks, excellent mechanical property with tensile strength of 3.8 MPa, and stable surface potential of − 270 V. By simply sandwiching the PTFE nanofibrous membrane into two pieces of conducting carbon clothes, a breathable, flexible, and high-performance nanogenerator (NG) device with a peak power of 56.25 μW is constructed. Remarkably, this NG device can be directly used as a wearable self-powered sensor for detecting body motion and physiological signals. Small elbow joint bending of 30°, the rhythm of respiration, and typical cardiac cycle are clearly recorded by the output waveform of the NG device. This study demonstrates the use of electrospun PTFE nanofibrous membrane for the construction of high-performance self-powered wearable sensors.
研究领域:
生物医学工程
·
纳米医学
·
柔性电子
·
可穿戴传感
·
能量收集
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）