Journal of the Taiwan Institute of Chemical Engineers
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2021
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IF 5.876
Jinxue Cheng,Naijia Zhao,Yan Huang,Changfa Xiao,Xiao Ma,Qinglin Huang
Background Membrane emulsification (ME) is an attractive membrane process to produce various kind of simple or multiple emulsions. The membrane utilized in ME process should have high dispersed phase flux, narrow pore size distribution and excellent antifouling property. Methods This work proposed a novel near-field electrospun (NFES) poly(tetrafluoroethylene) (PTFE) membranes with ordered rectangular pore geometry. Compared with other membranes, the order pore geometry of NFES PTFE membrane was helpful to obtain a more homogeneous and more stable water-in-oil (W/O) emulsion. Significant findings The droplet size was simply controlled by the NFES PTFE membrane pore size. And NFES PTFE membrane was more conducive to the formation of droplets with narrow droplet size distribution because of its unique straight rectangular membrane pore geometry. In addition, W/O emulsion droplet size be regulated in coordination with operating parameters and phase parameters. Results indicated that a smaller rectangular pore area of PTFE membrane would lead to a smaller droplet size. Introducing of shear stress in the continuous phase was contributed to the generation of monodisperse droplets. When the emulsifier (Span 80) content was 1wt%, the smallest droplet size (∼103.6 nm) was obtained.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
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IF 5.8
Biao He,Zhiwei Han,Jingyan Wang,Yaning Li,Jian Li,Saichao Song,Chen Li,Wei Liu,Chengyang Wu
Fluorine-based aluminum thermite have excellent ignition and combustion properties. Nonetheless, its combustion kinetics and energy release are hindered by slow mass diffusion and incomplete reactions. Therefore, this study successfully prepared an Al@PTFE composite with a core-shell structure, utilizing mechanical activation and sintering techniques, to enhance combustion properties and energy release rate. SEM, XRD, FTIR and XPS characterization results demonstrate the unique core-shell structure of the samples and the homogeneous distribution of elements on the surface. In comparison to the physical mixture, the Al@PTFE composite exhibits significantly higher values for P max (2.19 times), P max /Δt (11.30 times), and flame propagation velocity (4.5 times). Furthermore, the combustion duration required to reach the maximum flame height was reduced by 131.75 ms. The adsorption, decomposition and reaction processes of PTFE on the surface of aluminum particles were demonstrated based on RMD simulations. The promotion mechanism of PTFE on combustion in aluminum particles was elucidated.
研究领域:
材料科学
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燃烧化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Yawen Yang,Jinyu Zhu,Kaiming Hou,Limin Ma,Zhangpeng Li,Weihong Jia,Honggang Wang,Jinqing Wang,Shengrong Yang
In this work, a surprisingly simple and versatile strategy was developed to construct organic/inorganic bi-layer coating, and excellent lubricating properties and long service life are achieved simultaneously. The PTFE/Al 3+ -MXene coating was fabricated by a two-step strategy including self-assembly of Al 3+ -induced MXene coatings and in-situ transfer of PTFE under the induction of friction force and heat, which are designed to promote the molecular interaction and mechanical properties of composite coating, respectively. The ratio of Al 3+ /MXene concentration and pre-friction time against PTFE ball were regulated and optimized. It was found that the interaction exists between the transferred PTFE layer and MXene layer. Molecular dynamics simulations confirmed that the PTFE molecular chains could be anchored at the oxidation site of MXene sheets through friction-induced molecular welding, slowing MXene’s oxidation diffusion from the edge to the surface. The research results show that PTFE/Al 3+ -MXene coating after 1.0 h of pre-friction time presents the best service life among the prepared coatings, approximately 9 times longer than the PTFE transfer layer-1.0 h, and also much better than the Al 3+ -MXene 10 raw coating without transferring PTFE. It was further found that the obtained PTFE/Al 3+ -MXene/T-1.0 composite coating facilitates the easy formation of secondary transfer film on the upper counterpart, which is critical in extending the wear-resisting life of PTFE/Al 3+ -MXene/T-1.0 bi-layer coating.
研究领域:
材料科学
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机械工程
✓ 已验证
产品关联
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
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2025
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IF 6.1
Jianguo Liu,Yigong Guo,Zhanyu Wang,Xiao Xing,Gan Cui
Superhydrophobic coatings are renowned for their self-cleaning and water-repellent properties, making them increasingly valuable in industrial and consumer applications. Despite their widespread adoption, further enhancement of superhydrophobic performance remains a significant challenge. In this study, we introduce a novel approach to enhance the superhydrophobic capabilities of a composite coating by electrodepositing a Ni-WS 2 -PTFE composite coating under an applied magnetic field, notably improving its hydrophobic properties. The coupling of magnetic and electric fields induces a reorganization of the crystalline phase of nanoparticles within the plating solution, directly influencing the hydrophobicity of the composite coating. The water contact angle of the obtained Ni-WS2-PTFE composite coating reached 154°, with a minimum sliding angle of 4°. The coating also demonstrated excellent hydrophobic performance in both acid-base and weight-loss tests. After four weeks of immersion in a 3.5 % NaCl solution, the composite coating retained a corrosion resistance efficiency of 95 %. Magnetic fields play a beneficial role in the preparation of superhydrophobic coatings. While coatings produced through electrodeposition alone are not inherently superhydrophobic, the introduction of magnetic fields during the process imparts these desirable properties.
研究领域:
材料科学
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表面工程
✓ 已验证
产品关联
DOI
高影响因子
MRS Advances
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2018
·Vol. 4
·期 7
·359-367
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IF 0
Chen Chaolang,Weng Ding,Mahmood Awais,Wang Jiadao
In this study, a superhydrophobic and superoleophilic stainless mesh coated with polytetrafluoroethylene/silicon dioxide (PTFE/SiO 2 ) was fabricated through electrostatic self-assembly method followed by sintering treatment. The PTFE was utilized to construct low-surface-energy surface and the SiO 2 nanoparticles were added to enhance its surface roughness. The as-prepared stainless mesh exhibited desirable superhydrophobicity and superoleophilicity with a water contact angle of 152° and oil contact angle of 0°. The coated stainless mesh could separate a variety of oil/water mixtures with high efficiency and it also exhibited good recyclability. Moreover, the corrosion-resistance of stainless mesh was greatly improved by coating it with PTFE. The thermogravimetric analysis (TGA) measurements showed that the coated mesh could withstand high temperature of up to 430°C, indicating excellent thermal-resistance. It is believed that this ultra-robust stainless mesh would have significant potential applications in industry.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
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IF 5.518
Chaolang Chen,Xuqiao Peng
Desert sand is one of the most abundant natural resources, its reutilization is of significance and very valuable for the sustainable development of the environment. In this work, to realize the efficient reutilization of desert sand, we developed a facile method to fabricate superhydrophobic sands based on the self-assembly of PTFE nanocoating. The as-prepared sands exhibit simultaneously superhydrophobic and superoleophilic properties with a water contact angle is ∼150° and an oil contact angle is ∼0°. Besides, the applications of the as-prepared functional sands in water storage and oil/water separation were investigated in detail. The results show that the as-prepared sands exhibit good water storage capacity compared with the raw desert sand. Additionally, the as-prepared sand layer used as an adsorbent or filter can efficiently separate both light and heavy oil/water mixtures with a separation efficiency of > 96% and separation flux of > ∼24000 L/m 2 h. This work provides a good alternative for achieving the reutilization of desert sand and other natural resources.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
FIBERS AND POLYMERS
·
2021
·Vol. 22
·期 3
·664-675
·
IF 2.153
Liu Huizhong,Li Dawei,Shen Ying,Deng Bingyao
Due to the ultralow density and high specific area, nanofibrous sponges show great potential in the field of filtration and separation. To prepare nanofibrous sponges for high temperature smoke filtration, polytetrafluoroethylene (PTFE) was chosen due to its corrosion resistance and high temperature resistance. PTFE nanofiber prepared via electrospinning shows irregular concave-convex pores in the fiber body, which can improve the specific surface area and further enhance filtration performance. However, sponges made of PTFE nanofiber suffered from severe shrinkage, which limited the development in sponge products. In this study, polyimide (PI) nanofiber converted from polyamic acids (PAAs) nanofiber was introduced into the PTFE sponges to reinforce the dimensional stability. The parameters that influenced the morphology, porosity, shrinkage ratio, and thermodynamic properties of the composite sponges were also investigated. Moreover, the filtration performance of the composite sponges was tested. Results indicated that PTFE/PI composite nanofiber sponges possessed high porosity (94.34–98.12 %), excellent thermal stability (above 550 °C), and decent filtration efficiency (the maximum filtration efficiency reached 99.97 % to PM 2.0) were prepared, which demonstrated the potential in the field of high-temperature filtration.
研究领域:
材料科学
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环境工程
✓ 已验证
DOI
高影响因子
Defence Technology
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2022
·
IF 4.035
Yao-feng Mao,Qian-qian He,Jian Wang,Chuan-hao Xu,Jun Wang,Fu-de Nie
As a typical energetic composite, polytetrafluoroethylene (PTFE)/aluminum (Al) has been widely applied in explosives, pyrotechnics, and propellants due to its ultra-high energy density and intense exothermic reaction. In this work, the radial gradient (RG) structure of PTFE/Al cylinders with three different PTFE morphologies (200 nm and 5 μ m particles and 5 μ m fiber) and content changes are prepared by 3D printing technology. The effect of radial gradient structure on the pressure output of PTFE/Al has been studied. Compared with the morphology change of PTFE, the change of component content in the gradient structure has an obvious effect on the pressure output of the PTFE/Al cylinder. Furthermore, the relationships of the morphology, content of PTFE and the combustion reaction of the PTFE/Al cylinder reveal that the cylinder shows a more complex flame propagation process than others. These results could provide a strategy to improve the combustion and pressure output of PTFE/Al.
研究领域:
材料科学
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燃烧动力学
✓ 已验证
DOI
高影响因子
MATERIALS & DESIGN
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2020
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IF 6.289
Na Wang,Honggang Wang,Junfang Ren,Gui Gao,Shengsheng Chen,Gengrui Zhao,Yawen Yang,Jinqing Wang
In order to solve the problems of poor dispersibility and wettability, as well as unsatisfactory wear resistance and load capacity of polytetrafluoroethylene (PTFE) as water lubricating additive, a new type of PTFE@silica (PTFE@SiO 2 ) core-shell nanoparticles was prepared by encapsulating SiO 2 layer on the surface of PTFE via chemical bonding. Electron microscope analysis showed that the synthesized particles had well-defined core-shell morphology. Special double/multi-core structure and a reduced thickness of the intermediate shell were found, and the formation mechanisms were also explored in detail. The water contact angle measurement proved that the wettability of PTFE could be greatly enhanced by coating SiO 2 layer. The friction tests were performed to investigate the water lubrication properties of PTFE@SiO 2 additive, the results indicated that the core-shell PTFE@SiO 2 nanoparticles possessed the superior tribological properties, and the maximum friction coefficient and wear volume were respectively decreased by 75% and 99% when compared with pure water and water with PTFE/SiO 2 . Based on the analysis of worn surface, it was believed that the existence of core-shell structure and the formation of robust transfer film were the key to its excellent performance, and a possible lubrication mechanism was also proposed.
研究领域:
材料科学
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摩擦学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2020
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IF 5.774
Shiwen Yu,Qinglin Huang,Jinxue Cheng,Yan Huang,Changfa Xiao
Polytetrafluoroethylene (PTFE) nanofiber membranes with a kind of novel circular pore structure were fabricated in our study. Firstly, PTFE/PVA spinning solution was electrospun into precursor nanofiber membrane, during which, poly(tetrafluoroethylene-hexafluoropropylene) (FEP) aqueous dispersion was introduced by electrostatic spraying aiming to optimize the original fibrous network pore structure of electrospinning. After which, the prepared precursor nanofiber membranes were sintered, and PTFE nanofiber membranes were finally obtained. Effects of FEP contents on PTFE nanofiber membranes’ structure and performance were investigated, respectively. From the morphology observation, it was found that the PTFE nanofiber membrane’s pore structure gradually transformed from fibrous network to circular pore due to the melting of FEP resins. Owing to the excellent under-oil hydrophobicity and the uniform circular pore structure, the obtained PTFE nanofiber membranes were utilized in membrane emulsification (ME) process to prepared water in oil (W/O) emulsion. Compared with the conventional mechanical stirring method, the W/O emulsion prepared by ME process showed not only more uniform water droplet size (about 270 nm), but also more stable and higher production efficiency.
研究领域:
材料科学
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化学工程
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Lanting Yang,Zhaokang Chen,Lihao Wang,Zhenwei Zhang,Ruihao Wang,Changping Guo
The high sensitivity of high explosive hexanitrohexaazaisowurtzitane (CL-20) limits its applicability, and the performance optimization brought by the synergistic effect between nanothermite and CL-20 is expected to expand its application prospects. In this study, polydopamine (PDA) was introduced to modify CL-20 (denoted as pCL-20), and a quasi-core/shell pCL-20/polytetrafluoroethylene-aluminum (pCL-20/PTFE-Al) composite was successfully prepared by ultrasonic-assisted composite method. The performance characterization results demonstrate that the composite exhibits significantly better decomposition heat release than the mixed sample, a reduction in combustion time from 408 ms to 268 ms, a more stable combustion flame, and more focused energy release. At the same time, the comparison of composite combustion with different condition variables reflects the combustion advantages of the selected proportional conditions in this study. The characteristic drop height (H 50 ) increased from 24.05 cm to 42.15 cm, the explosive percentage of friction sensitivity reduced from 100 % to 70 %, and the sensitivity of the composite sample decreased significantly when compared to the raw CL-20. It improves the combustion performance while reducing the sensitivity, thereby enhancing the application potential and providing a reference for the high-energy desensitization of energetic materials.
研究领域:
材料科学
·
爆炸物化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Min Sang,Guanghui Liu,Shuai Liu,Yuxuan Wu,Shouhu Xuan,Sheng Wang,Shanyong Xuan,Wanquan Jiang,Xinglong Gong
In recent years, soft electrothermal actuators (ETAs) have attracted great concern because of their potential applications in biomimetic intelligent devices, soft robotics and aerospace engineering. However, achieving the simultaneous optimization of low-voltage actuation, ultrafast preparation and highly integrated functionality are main challenges to the development of ETAs. Herein, a flexible, hydrophobic, mechanically robust and electromagnetic-interference (EMI) shielding PTFE/MXene/PI soft ETA is constructed through a very simple and fast “cutting and sticking” method by taping PTFE and PI tapes onto the surface of MXene film. The commercially available PTFE and PI tapes endow PTFE/MXene/PI sandwich structure with ideal mechanically robustness and hydrophobic self-cleaning function, thus it can work in different environments. Remarkably, PTFE/MXene/PI sandwich structure shows an outstanding EMI shielding ability with the maximum SE T value of 44 dB owing to the high electrical conductivity of MXene film. More importantly, the PTFE/MXene/PI sandwich actuator can bend from PTFE side toward PI side under the electrical stimulus, because the excellent electrothermal MXene layer is sandwiched between the two tapes with large difference in thermal expansion coefficients. Under a 6 V low voltage, the actuator can generate heat energy with the maximum saturation temperature of 110 °C and large bending deformation with the maximum bending angle of 122° within 40 s. Interestingly, the PTFE/MXene/PI structure can be designed and manufactured in different shapes and configurations upon actuation, such as the “S” shape and four-finger gripper. At last, a smart shielding curtain with the combination of actuation properties and EMI shielding performance is finally developed as a principle of concept, which further indicates the multifunctional PTFE/MXene/PI ETA can be widely applied in smart EMI shielding system and soft robotic devices.
研究领域:
材料科学
·
智能设备
·
软体机器人
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）