COMPOSITES COMMUNICATIONS
·
2023
·
IF 8
Yan Huang,Qiang Guo,Yuxin Zhang,Fuxin Qiu,Xuancheng Zhang,Guanghui Wang,Jian Zhao,Qinglin Huang,Changfa Xiao
PTFE nanofiber membrane, as an effective supplement to biaxial stretched PTFE membrane, suffers from low modulus and poor structural stability. In this study, the PTFE porous membrane with high modulus and structural stability was designed and achieved via the in-situ interlocking and anchoring strategy by co-electrospinning polyacrylonitrile (PAN) into PTFE matrix. During the sintering process, the continuous flexible PTFE nanofibers formed, while PAN nanofibers was pre-oxidized to create a stable trapezoidal structure. The effects of pre-oxidized PAN (OPAN) nanofibers' content and diameter on the morphology and structure of the PTFE/OPAN composite nanofiber membrane were investigated in detail. Results showed that the introduction of OPAN nanofiber effectively improve the modulus and structural stability of PTFE nanofiber membrane. The Young's modulus and tensile strength of the composite nanofiber membrane were over 50 MPa and 2 MPa, which were 1166% and 80% higher than that of pure PTFE nanofiber membrane, respectively. These results of this work would contribute to solve the defects of PTFE nanofiber membrane's low modulus and poor structural stability, and then expand its application scope.
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Yanan Li,Tingting Fan,Wenying Cui,Xia Wang,Seeram Ramakrishna,YunZe Long
Efficient treatment organic pollutants and oily wastewater with high toxicity under harsh environment is eagerly desired, while conventional membranes cannot meet the demand due to its poor chemical resistance which still remains a great challenge. Herein, biomimic polytetrafluoroethylene (PTFE) @ zeolite imidazole framework (ZIF-8) fibrous membrane for efficient photocatalytic organic pollutants degradation and oil-water separation under harsh environments was successfully developed, via electrospun PTFE nanofibrous membrane with numerous micro-nano rough papillae followed by in situ growth highly porous ZIF-8. The high surface area PTFE@ZIF-8 membrane with lotus-leaf-like structure exhibits excellent photocatalytic degradation performance to organic pollutants such as dyes (methylene blue and rhodamine B) and antibiotics (tetracycline) in harsh environments (strong acids/bases) with a remarkable high removal efficiency (99.99%). Meanwhile, the fluorinated PTFE@ZIF-8 membranes with super-hydrophobicity and super-lipophilicity property also exhibit outstanding oil/water separation performance (chloroform, kerosene, dichloromethane, toluene and n-hexane), with an extremely high flux of 2157 L m −2 h −1 (dichloromethane/water) and separation efficiency of 99.99% (kerosene/water). Furthermore, the membrane also able to separate water-in-oil emulsions effectively with an efficiency of as high as 99.99%. Most importantly, the robust PTFE@ZIF-8 membrane possesses excellent corrosion resistance, self-cleaning and recycling properties, which could still maintain such high separation efficiency and flux even after more than 10 cyclic oil-water separation tests under harsh environments. The multifunctional membrane with excellent harsh environment-tolerance offers an inspired strategy for efficient wastewater treatment under complex conditions and shows great potential for practical applications.
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2021
·Vol. 15
·期 1
·62
·
IF 3.623
Ying Liu,Gengyuan Gao,Dan Jiang,Zhongwei Yin
This paper studied a hybrid polytetrafluoroethylene (PTFE)/Nomex fabric composite with lower friction coefficient (COF) and high underwater wear resistance. A pin-on-disk tribometer was used to test tribological properties under different applied loads and rotation speeds. The wear surface, transfer film and cross-section were analyzed by scanning electron microscope (SEM) and optical microscope. The results showed enhanced underwater tribological properties because of excellent self-lubricating properties of PTFE fibers and a good lubricating effect and load-carrying capacity of graphite fillers. Improved underwater mechanical strength was connected to the high strength of epoxy resin and high bonding force between Nomex and epoxy resin.Keywords:fabric composite;epoxy;graphite;friction and wear;water-lubricated
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Membranes
·
2021
·Vol. 11
·期 6
·420
·
IF 4.106
Tianshu Liu,Xiaoji Zhou,Yizhuo Sun,Renbi Bai
In this study, PVDF/PTFE composite membranes were prepared by adding a PTFE nanoemulsion to a PVDF solution and casting it through the conventional non-solvent-induced phase separation method. The objective was to explore the effectiveness of using a simple and economical method to modify PVDF membranes with PTFE to enhance their anticorrosion performance, especially under highly acidic or alkaline conditions. PTFE nanoparticles (of around 200 nm in size) in nanoemulsion form were blended with PVDF at a mass ratio of PTFE:PVDF in the range of 0–0.3:1. The obtained membranes were examined to determine the effect of the added PTFE nanoparticles on the structure of the modified PVDF membranes as well as on their mechanical strength and surface characteristics. The membranes were then immersed in various concentrations of acidic or alkaline solutions for varied durations ranging from a few days up to as long as 180 days (6 months). The impacts of by the corrosive solutions on the tensile strength, surface roughness, and water flux of the membranes with different exposure times were quantified. The results showed that although a certain extent of change may occur with extended immersion times, greatly enhanced anticorrosion performance was obtained with the prepared PVDF/PTFE membranes compared with the unmodified PVDF membrane. For example, after being immersed in 5 mol-H+··L−1H2SO4, HCl, and HNO3solutions for 6 months, the tensile strength at breaking point remained at up to 69.70, 74.07, and 71.38%, respectively, of the initial strength for the PVDF/PTFE (M30) membrane. This was in contrast to values of only 55.77, 70.43, and 61.78% for the unmodified PVDF membrane (M0). Although the water flux and surface roughness showed a change trends to the tensile strength, the PVDF/PTFE (M30) membrane had much higher stability than the PVDF (M0) membrane. In a continuous filtration experiment containing H2SO4at 0.01 mol-H+·L−1for 336 h (14 days), the PVDF/PTFE membrane showed a maximum flux change of less than 30%. This was in comparison with a change of up to 50% for the PVDF membrane. However, the PVDF/PTFE membranes did not seem to have a greatly enhanced anticorrosion performance in the alkaline solution environment tested.Keywords:PVDF/PTFE composite membrane;PTFE nanoparticle;polymer blending;non-solvent induced phase separation method;anticorrosive performance
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FIBERS AND POLYMERS
·
2021
·Vol. 22
·期 11
·3025-3034
·
IF 2.153
Li Chengcai,Tang Tao,Zheng Tao,Hong Wei,Wang Feng,Liu Guojin,Lei Caihong,Yu Yuan,Zhu Hailin,Guo Yuhai
A new hydrophilicity and negatively charged polytetrafluoroethylene (PTFE) fiber membrane has been developed and characterized. Specifically, the dopamine (DA) and polyethylenimine (PEI) were co-deposited onto the PTFE fiber membrane surface via covalent connection. Then the amine groups of the membrane surface were reacted with anhydride groups of poly(ethylene-alt-maleic anhydride) (PEMA). Last, unreacted anhydride groups have hydrolysis and ionization. The preparation membrane has been investigated and confirmed by using XPS, ATR-FTIR, SEM, Zeta potential analyzer, pore size analyzer water contact angle, respectively. The results showed that the membranes were endowed with excellent hydrophilicity and negatively charged. It has high separation efficiency and permeation flux for oil-in-water emulsion containing cationic emulsifiers, and excellent anti-fouling property.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 138
·期 8
·49872
·
IF 2.52
Wanjie Luo,Lulu Wang,Ruijiang Feng,Chongfeng Zhao,Jilin Wang,Tianzhou Cai
A series of composite anion exchange membranes was synthesized via in-situ copolymerization of various ratios N-vinyl formamide (NVF) and divinylbenzene (DVB), supported by porous polytetrafluoroethylene (PTFE) polymer matrix, and followed by alkaline hydrolysis, and quaternization of the composite membranes with epoxypropyltrimethylammonium chloride (EPTMAC). FTIR and SEM analyses revealed that the composite membranes were successfully prepared. Moreover, the hydrophilic property of the composite membrane improved by introduction of the quaternized poly(NVF-co-DVB) copolymer. Water uptake, swelling ratio, and conductivity showed upward trends by increase of NVF amount. The copolymer with 95% of NVF showed the highest elongation at break (102%, room temperature) and conductivity (5.15 × 10 −2 S/cm, 80°C). After immersion of the PNDB 95% -N membrane in 5 mol/L NaOH solution for 96 h at room temperature, the conductivity (60°C) of the membrane decreased to 3.99 × 10 −2 S/cm. Moreover, the membrane registered weight loss under 4.5%, caused by degradation of the quaternary ammonium groups in NaOH solution. All in all, in 3 mol/L methanol solutions, the composite membranes showed permeability ranging from 7.6% to 19.7%, if compared to the Nafion®-115 membrane, showing good alcohol resistance.
✓ 已验证
产品关联
DOI
高影响因子
Advanced Sustainable Systems
·
2024
·
IF 6.5
Xu Chen,Yingjie Wen,Yuechu Wang,Li Yi,Hao Yang,Zhiyi Lu
Heterogeneous catalysts for catalytic ozonation are elaborately designed with commendable intrinsic activity, while their industrial applications are limited by inadequate mass transfer of ozone (O 3 ). In this work, it is demonstrated that engineering the surface aerophilicity of heterogeneous catalyst enables fast mass transfer of O 3 reactant, giving rise to much enhanced catalytic ozonation performance. Taking active 4A zeolite catalyst as an example, the aerophilicity of spherical 4A zeolite can be greatly enhanced by coating polytetrafluoroethylene (PTFE) with low surface energy, and the optimized sample exhibits a 99.5% removal of atrazine (ATZ) within 20 min (corresponding to a k of 0.269 min −1 ), much better than 4A zeolite without surface aerophilicity engineering ( k ≈0.156 min −1 ). The PTFE coating does not change the ozone activation mechanism and degradation pathways for ATZ, further demonstrating that the enhanced ozonation activity is attributed to the enhanced mass transfer process. In addition, the general applicability of this surface aerophilicity and the potential ozonation application for industrial wastewater treatment are both demonstrated.
研究领域:
环境科学
·
催化
·
化学工程
·
水处理
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Da-Qi Cao,Rong-Kun Fang,Yi-Xuan Song,Ming-Guo Ma,Haiyan Li,Xiao-Di Hao,Rongling Wu,Xiangyu Chen
Antibiotic contamination of water bodies is a major concern in environmental management. Despite their superior efficacy in antibiotic removal, advanced oxidation processes (AOPs) have yet to be widely adopted owing to their substantial cost associated with the large amounts of chemicals required. In this study, a novel contact-electro-catalysis (CEC) process with reusable polytetrafluoroethylene (PTFE) particles as a trigger catalyst was applied to replace traditional AOPs, and it was able to degrade three typical antibiotics (sulfamethoxazole [SMX], ciprofloxacin [CIP], and tetracycline [TET]) in the secondary effluent of a wastewater treatment plant for the first time. The PTFE particles at a concentration of 0.8 g/L were introduced into antibiotic solutions with an antibiotic concentration of 1 mg/L, and the removal rates of SMX, CIP, and TET after a 90-min operation time reached 50 %, 80 %, and 90 %, respectively. Our findings revealed that the CEC reaction generated ● OH and 1 O 2 , contributing substantially to antibiotic degradation. Thus, new reactive oxygen species generation mechanisms during the CEC process were proposed. Furthermore, we fabricated polyvinylidene fluoride nanofiber membranes using electrospinning to recycle PTFE particles, where a nearly 100 % recovery rate through dead-end filtration was realized with a high water flux of 7.5 m 3 /(m 2 ∙h). The results of this study provide a promising approach for antibiotic removal from wastewater.
研究领域:
环境工程
·
水处理
·
催化
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Yan Li,Chunrui Peng,Haoxiao Liang,Dongxing Zhang,Tao Wu,Qiuquan Guo,Junfeng Xiao,Peipei Jia,Jun Yang
Polytetrafluoroethylene (PTFE) is renowned for its exceptional chemical inertness and hydrophobicity. However, the high melt viscosity, low surface energy, and high cooling shrinkage of PTFE make it difficult to fabricate fine three-dimensional (3D) structures through photopolymerization molding. Meanwhile, due to the mechanical properties of PTFE, such as low hardness and low elastic modulus, the wear resistance of its structure is usually poor. In this study, we propose an effective strategy to enhance both wear resistance and superhydrophobicity in 3D-printed PTFE/C structures by controlling the carbon residue during the sintering process. To achieve the refined structure of PTFE, a photo-cross-linkable PTFE/PEGDA ink was developed, in which PEGDA acts as a photocurable scaffold to enable high-resolution DLP printing of PTFE nanoparticles. Furthermore, inspired by the microarray of cicada wings, a needle-repellent structure with a water contact angle (CA) exceeding 150° was printed using a PTFE-based ink. Based on the above structure, the carbon residue in PTFE/PEGDA was controlled by the sintering process to further enhance the wear resistance and superhydrophobicity of the structure. These results indicated that the sintered needle-repellent structure can still maintain excellent hydrophobic properties with 1000-grit sandpaper under a load of 100 g for 20 cycles. The performance conflict between superhydrophobicity and wear resistance of the PTFE/C structure has been effectively alleviated through the printed needle-repellent structure and controlled carbon residue. Furthermore, even after 2 weeks of immersion in strongly acidic and alkaline environments, the structure morphology remains stable. These excellent features of the needle-repellent structure make it applicable to a wide range of applications, such as droplet manipulation, oil–water separation, and fog harvesting.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2026
·
IF 7.3
Yunfeng Yang,Weibing Xu,Zhengfa Zhou,Haihong Ma,Fengmei Ren
Polyimide (PI) exhibits high-temperature resistance and corrosion resistance, making it a high-potential coating substrate. However, for use in automotive motor bearings, its adhesion and wear resistance still require improvement. This study investigated the efficient exfoliation of MoS 2 and combined few-layer MoS 2 with Polytetrafluoroethylene (PTFE) as a synergistic wear-resistant agent, which can be incorporated into PI coatings to improve the wear resistance. It achieved a minimum coefficient of friction (COF) of 0.073 and a wear rate of 0.0554 × 10 −5 mm 3 /(N·m). This result is attributed to the layered structure of few-layer MoS 2 and its synergistic interaction with PTFE. The structure of PI contains numerous ether bonds and highly polar sulfone groups that can bind to metal surfaces. The resulting coating achieves level 0 adhesion (ISO 2409:2020) on metal substrates for bearings, while exhibiting high toughness, impact resistance, and coolant resistance. This work is of great significance to research on high-adhesion coatings and nanoscale synergistic lubrication.
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2019
·
IF 3.42
Chengcai Li,Zehua He,Feng Wang,Hailin Zhu,Yuhai Guo,Meiyu Chen
To improve hydrophility and antifouling property of Polytetrafluoroethylene flat microfiltration membrane, a novel and facile method was developed to modify the membrane via the polymer of Laccase-catalyzed self-polymerization of Gallic acid and cross-linked with Polyethylenimine, then the surface micro/nanostructures was treated by (2,3-epoxypropoxy)-propytrimethoxysilane. The surface chemical composition, surface morphology, hydrophilicity and antifouling property of the PTFE flat membrane were investigated by ATR-FTIR, XPS, FESEM, water contact angle, pure water flux measurements, respectively. After using this low-cost and simple modification method, PTFE flat membranes were endowed with excellent hydrophilicity, high pure water flux and antifouling property. Besides, the modified PTFE flat membrane could be applied to the separation of oil-in-water emulsion with an ultrahigh efficiency 98.2% and also shows durable oil resistance and antifouling performance, making the membrane easy to reuse. Finally, the surface stability of the modified membrane was studied and the mineralized membrane showed excellent acid resistant ability. Therefore, this facile strategy holds attractive potential practical application in water environmental remediation.
研究领域:
环境科学
·
材料科学
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2022
·
IF 7.139
Zhipeng Tian,Weijie Zhang,Tao Liu,Jianping Liu,Chenguang Wang,Libin Lei,Mingzheng Liao,Chao Wang,Ying Chen
Hydrogen production by catalytic aqueous phase reforming (APR) of biomass-derived oxygenates is a promising route to produce hydrogen in a renewable way. As the typical APR catalyst, Pt/Al 2 O 3 is confronted with high methanation activity that consumes H 2 and produces undesired CH 4 during the treatment of methanol solution. In contrast, WGS reaction is the main pathway to boost H 2 generation during APR process. In this work, a series of PtFe/Al 2 O 3 catalyst with different Fe contents were prepared, characterized and tested for the methanol APR reaction. XRD , TEM, XPS and H 2 -TPR technologies were applied to study the change of physicochemical properties with the addition of iron. The restriction on methanation and promotion on WGS reaction were proved as well. With the increase of Fe content, the interaction between Pt and FeO x species have both positive and negative effects on APR reactivity while the CH 4 selectivity descending continuously from 9.25% to as low as 0.60%. Besides, the effects of reduction temperatures (250–350 °C) of Pt0.5Fe/Al 2 O 3 catalyst on APR performances were also investigated. An “Oxygen dynamic transfer cycle” between H 2 O/CO∗ and FeO x species with oxygen vacancies is proposed and verified. This indirect WGS reaction through lattice oxygen on FeO x species that boosting WGS reactivity helps improving H 2 selectivity in the gas products of methanol APR.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）