Reaction Chemistry & Engineering
·
2024
·
IF 3.4
Minmin Liu,Bingxi Song,Yanhui Hu,Xianglei Meng,Renzheng Jiang,Yanyan Diao,Yuting Song
Following the principle of sustainable and green development, the environmentally friendly and highly efficient manufacturing of fluorine chemical products is becoming an unavoidable development trajectory. Ionic liquid catalysts have shown great potential to replace traditional metal salt catalysts, which cause environmental pollution, in the dimerization of perfluorinated olefins. In this study, a series of strong nucleophilic thiocyanate ionic liquids with various cationic structures were designed and synthesized. The catalytic activity of 4-dimethylaminopyridine (DMAP) ionic liquids exceeded that of reported catalysts, being 2.4 times higher than that of traditional metal salt catalysts, and 1.5 times higher than that of imidazole ionic liquids reported in the literature. Under the optimal reaction conditions, the high turnover frequency (TOF) value of the [C6DMAP][SCN] catalyst performance reaches 325.04 h−1. Based on the experimental results, density functional theory (DFT) and XPS analysis, the excellent catalytic performance of [C6DMAP][SCN] can be attributed to the dual active sites of anions and cations, and a dual-activation reaction mechanism is further proposed. This study not only expands the application of ionic liquid in the hexafluoropropylene dimerization reaction but also helps establish a more efficient, green, and sustainable catalytic process for hexafluoropropylene dimerization.
研究领域:
化学工程
·
绿色化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2024
·
IF 5.7
Peng Liu,Linshan Wu,Xiulin Huang,Zhiguang Guo
Membrane materials are widely used in the treatment of oily wastewater. In this work, hybrid nanofibrous membranes of polyacrylonitrile (PAN) and polytetrafluoroethylene-hexafluoropropylene (PVDF-HPF) were prepared by electrospinning and cured at high temperature. Subsequent hydrothermal treatment to grow Mg/Al-LDHs and polymerization of tannic acid (TA) on the surface yielded WPPLT membranes. SEM and EDS tests showed that the WPPLT membranes had a uniform compositional distribution. AFM tests showed that the hydrothermal and tannic acid treatments increased the roughness of the membranes and imparted a superhydrophilicity to the membranes. Separation tests of the emulsion showed that the separation efficiency was above 99 % with stable flux due to the fine pore size of the nanofiber membrane and the positive charge effect of the LDHs. Mechanical tensile tests showed that the tensile strength of the WPPLT membrane was 4.1 MPa, which was 89 % higher relative to the electrospinning membrane. Finally, the synergistic effect of LDHs and tannic acid under UV irradiation achieved more than 90 % degradation efficiency of methylene blue (MB). The present work provides new insights to improve the mechanical properties of nanofiber membranes, which helps the membranes to be used in more complex environments and enhances the prospect of their application in oil and water pollution.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2024
·Vol. 225
·期 23
·2400233
·
IF 2.5
Lu Meng,Zexia Li,Weilong Wu,Bo Li,Zifeng Niu,Peng Wang,Jun Zhang,Chengchun Tang,Yanming Xue
Polyimide (PI) is one of the most important engineering plastics, but its stability in aqueous environments is insufficient, which limits its anti-corrosion efficiency. In this study, a novel P(VDF-HFP)/SMT-RS@BNNSs/PI composite coating is prepared by incorporating poly(vinylidene fluoride-hexafluoropropylene) (P(VDF-HFP)) and the exfoliated boron nitride nanosheets (BNNSs) which were highly co-functionalized with two kinds of materials of the rosin and the soy-maleic anhydride-tannic acid adhesive molecules (SMT-RS@BNNSs). The coatings are characterized in detail by using the XRD, FT-IR, XPS, and SEM technologies. Electrochemical impedance spectroscopy (EIS) and polarization curve tests further evaluated the corrosion resistance of the coating. As results, the obtained P(VDF-HFP)/SMT-RS@BNNSs/PI coating with good adhesion (grade 1) to the low-carbon steel plate displays a larger water contact angle of 93.10° compared to blank PI (75.5°) and SMT-RS@BNNSs/PI (83.2°). The dispersed distribution and interaction of SMT-RS@BNNSs can effectively reduce the phase separation between P(VDF-HFP) and PI. Even after soaking in electrolyte for 15 days, the impedance modulus, corrosion current, and corrosion voltage of the P(VDF-HFP)/SMT-RS@BNNSs/PI coating are 1.568 × 10 10 Ω cm 2 , 4.612 × 10 −12 A cm −2 , and 0.325 V, respectively. These properties are superior to those of the PI and SMT-RS@BNNSs/PI coatings. It is believed that the excellent anti-corrosive performance of this PI-based composite will broaden the application fields of PI materials.
研究领域:
材料科学
·
腐蚀与防护
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2023
·
IF 11.4
Lei Chen,Daijie Chen,Shunyi Zhou,Jieying Lin,Yun Liu,Xiongfei Huang,Qingqi Lin,Jean Louis Morel,Zhuobiao Ni,Shizhong Wang,Rongliang Qiu
Hexafluoropropylene oxide (HFPO) homologues, which are important alternatives to perfluorooctanoic acid, have been frequently identified in crops. Although exposure to HFPO homologues via crops may pose non-negligible threats to humans, their impact on crops is still unknown. In this study, the accumulation, transport, and distribution mechanisms of three HFPO homologues in lettuce were investigated at the plant, tissue, and cell levels. More specifically, HFPO trimer acid and HFPO tetramer acid were primarily fixed in roots and hardly transported to shoots (TF, 0.06–0.63). Conversely, HFPO dimer acid (HFPO-DA) tended to accumulate in lettuce shoots 2–264 times more than the other two homologues, thus resulting in higher estimated daily intake values. Furthermore, the dissolved organic matter derived from root exudate enhanced HFPO-DA uptake by increasing its desorption fractions in the rhizosphere. The transmembrane uptake of HFPO homologues was controlled by means of a transporter-mediated active process involving anion channels, with the uptake of HFPO-DA being additionally facilitated by aquaporins. The higher accumulation of HFPO-DA in shoots was attributed to the larger proportions of HFPO-DA in the soluble fraction (55–74%) and its higher abundance in both vascular tissues and xylem sap. Our findings expand the understanding of the fate of HFPO homologues in soil–crop systems and reveal the underlying mechanisms of the potential exposure risk to HFPO-DA.
研究领域:
环境科学
·
植物学
✓ 已验证
DOI
PubMed
高影响因子
Advanced Materials Interfaces
·
2018
·Vol. 6
·期 1
·1801330
·
IF 4.834
Muhammad Waqas,Shamshad Ali,Weiqiang Lv,Dongjiang Chen,Bismark Boateng,Weidong He
Highly efficient and thermally stable polyethylene-hexagonal boron nitride/poly(vinylidene fluoride-hexafluoropropylene) (PE-BN/PVDF-HFP) bilayer separator with microporous structure is prepared, for the first time with a wet chemistry method. The incorporation of hexagonal boron nitride particles in PE matrix promotes the interfacial interaction between PE and PVDF-HFP layers to prevent separation of layers and supresses dendrite growth owing to the strong adsorption energy with polymers, large interactive surface area, and superior mechanical capability. The PVDF-HFP layer provides additional thermally stable backbone while its inherent hydrophilic property and highly porous structure improve the overall performance of the separator. The bilayer separator owns a high electrolyte uptake of 348% and a thermal shrinkage of 6.6% upon annealing at 140 °C for 1 h. The lithium iron phosphate/lithium cell with the as-prepared separator owns a high ionic conductivity up to 4.4 × 10 −4 S cm −1 , and a room-temperature capacity of 120 mAh g −1 at 2 C with a 95% capacity retention after 500 cycles and a capability of 108 mAh g −1 at 4 C. The PE-BN/PVDF-HFP separator is a promising alternative of traditional multilayer separators for high-performance lithium-ion batteries.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
ChemElectroChem
·
2018
·Vol. 5
·期 19
·2722-2728
·
IF 4.446
Muhammad Waqas,Chao Tan,Weiqiang Lv,Shamshad Ali,Bismark Boateng,Wenjin Chen,Zhaohuan Wei,Chao Feng,Junaid Ahmed,John B. Goodenough,Weidong He
Graphical Hot in, so hot in here ! By incorporating colloidal TiO 2 in PVDF-HFP, a composite separator is fabricated showing a robust micro-structure sustaining high-temperature treatment. LFP/Li batteries based on the PVDF-HFP/colloidal-TiO 2 separator deliver a charge-discharge capacity of 156.9 mAh g −1 (0.1 C) at room temperature and 120.8 mAh g −1 (0.5 C) after annealing batteries at 140 °C for 3 hours with a 99 % capacity retention. A PVDF-HFP/colloidal-TiO 2 composite separator is synthesized for high-temperature lithium-ion batteries. Incorporation of colloidal TiO 2 in the PVDF-HFP matrix forms a highly-uniform composite micro-structure with strong adsorption interactions between TiO 2 and PVDF-HFP due to the presence of citric acid. The strong interactions are giving rise to advantageous mechanical robustness, separator/electrode interface and electrolyte uptake. The separator shows remarkable stability upon thermal treatment at 150 °C. With a high ionic conductivity up to 1.57×10 −3 S cm −1 , the LFP/Li cell with PVDF-HFP/colloidal-TiO 2 composite separator delivers charge-discharge capacities of 156.95 mAh g −1 (0.1 C) at room temperature and 120.8 mAh g −1 (0.5 C) after annealing cells at 140 °C for 3 hours with a 99 % capacity retention after 100 cycles. The PVDF-HFP/colloidal-TiO 2 separator demonstrates promising potentials for practical applications in high-temperature environments.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2020
·Vol. 8
·期 30
·10257-10265
·
IF 7.059
Liang Sun,Zhicheng Shi,Liang Liang,Shuang Wei,Huanlei Wang,Davoud Dastan,Kai Sun,Runhua Fan
Polymer dielectric composites are of considerable interest for film capacitors that are widely used in modern electric devices and electric power systems. However, the adverse coupling between dielectric permittivity (εr) and breakdown strength (Eb) makes it difficult to obtain high energy densities in natural materials. With the aim of achieving concurrently improved εr and Eb, a class of rationally designed layer-structured composites consisting of pure poly(vinylidene fluoride–hexafluoropropylene) (P(VDF–HFP)) layers and barium titanate/P(VDF–HFP) (BT/P(VDF–HFP)) composite layers were prepared. Interestingly, the layer-structured composites exhibit a concurrent improvement of εr and Eb. The 4-layer composite with 15 vol% BT exhibits substantially enhanced εr and Eb which are nearly ∼186% and ∼248% of those for its 1-layer counterpart, respectively. Consequently, a high energy density of ∼4 J cm−3 along with a satisfactory efficiency of 71% at 240 kV mm−1 is achieved. Meanwhile, a low loss tangent of ∼0.05 at 10 kHz which is comparable to that of pure P(VDF–HFP) is maintained. This work shows that the adverse coupling between εr and Eb in dielectric materials could be well addressed by constructing nanocomposites with layered rather than random distribution of fillers.
研究领域:
材料科学
·
电气工程
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 37
·29017-29021
·
IF 3.84
Z. D. Liu,Y. Feng,W. L. Li
We reported the preparation of carbon nanotubes adhering BaTiO3 nanoparticles (BT@CNTs) via chemical vapor deposition (CVD). Scanning electron microscopy, transmission electron microscope and Raman spectroscopy were carried out in order to confirm the successful adhesion. Dielectric properties of the PVDF-HFP composites filled by BT@CNTs were also studied. With the content of BT@CNTs increasing, the dielectric constant of composites remarkably increased, but the loss tangent gradually decreased. At 10 vol%, the dielectric constant of the PVDF-HFP/BT@CNTs composite was significantly increased to 27.7 at 50 Hz, which was 3 times and 65% higher than that of the pure PVDF-HFP and PVDF-HFP/BT composite, respectively. The loss tangent of the PVDF-HFP/BT@CNTs composite was lower even than that of pure PVDF-HFP. These attractive features of the PVDF-HFP/BT@CNTs composites suggested that the method proposed herein was a new approach to develop high performance composites, especially those with high dielectric constant and low dielectric loss.
研究领域:
材料科学
·
电气工程
✓ 已验证
DOI
高影响因子
Advanced Science
·
2025
·
IF 14.1
Yijun Han,Quanjie Lv,Linxuan Zhang,Yuruo Zhang,Xinyue Yu,Yongjie Wu,Jing Chu,Gengxin Zhang,Kang Sun,Ke Tao
Adsorption–desorption technology is the basis of numerous environmental processes and industries in modern society. Undoubtedly, improving adsorption rates and renewability of sorbents can positively impact productivity. It is herein showed that poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) presented remarkable adsorption kinetics and regeneration efficiency under ultrasound. The pseudo-first-order adsorption rate constant for Rhodamine B (RhB) is 2.7753 min −1 , with an initial adsorption rate 7,000–23,000 times higher than commercial activated carbon. Meanwhile, the polymer achieves over 90% removal of the antibiotic levofloxacin (LEV) and the persistent pollutant perfluorooctanoic acid (PFOA) within 5 min. Impressively, complete desorption occurs within 2 min by simply changing the solvent, and the performance is retained across at least 20 adsorption–desorption cycles. It is proposed that, under ultrasound, the low interface tension of PVDF-HFP may accelerate solute diffusion by disrupting the liquid film, while the ferroelectric PVDF-HFP generates a built-in electric field to enhance adsorption. This research suggested an alternative strategy for developing high-performance adsorption–desorption techniques.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2025
·
IF 8
Yueshu Lu,Yuqing Li,Wenqiang Yang,Kaiyuan Ma,Yanfeng Zhang,Lingyan Zhu
As a widely used alternative to the conventional per- and polyfluoroalkyl substances (PFAS) of perfluorooctanoic acid (PFOA), hexafluoropropylene oxide trimer acid (HFPO-TA) is of growing concern due to its toxicity and potential risks to human health. Water quality criteria of HFPO-TA for protecting human health were established, and 412 ng/L was set as the maximum concentration level for groundwater ( MCL gw ) to calculate the soil control value to protect groundwater ( CVS pgw ). Utilizing recommended default values for the properties of HFPO-TA and the soil, the generic CVS pgw value of 24.0 μg/kg was obtained. Subsequently, column experiments were conducted to investigate the transport of HFPO-TA in the site soil of a fluorochemical industrial park (FIP) in China. The resulted retardation factor ( R ) was applied to derive the site-specific CVS pgw , and a value of 2.48 μg/kg was obtained. Using the experimentally measured R instead of the default empirical values reduced the uncertainties in deriving the CVS pgw dramatically. The transport of 13 PFAS in the soil as a mixture was investigated and revealing a significant linear correlation between R and organic carbon-water partition coefficient ( K OC ) ( r 2 = 0.991, p < 0.01), which was utilized to predicted R values for PFAS compounds. Comparison to the site-specific CVS pgw , HFPO-TA in the soil near the FIP may pose a risk to the groundwater quality. HFPO-TA concentrations in the groundwater of certain areas around the FIP were higher than MCL gw and not recommended for directly consumption, while HFPO-TA in the tap water was at the safe level.
研究领域:
环境科学
·
毒理学
✓ 已验证
DOI
PubMed
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2021
·
IF 3.975
Yingdong Duan,Qizheng Li,Biyun Peng,Shaobo Tan,Zhicheng Zhang
In the present work, diverse vinyl monomers were successfully grafted onto poly(vinylidene fluoride-hexafluoropropylene) P(VDF-HFP) via direct activation of C F bonds using Cu(0)/4,4′-dimethyl-2,2′-bipyridyl (DMDP) as catalyst under mild conditions. The structure of the graft copolymer was carefully characterized, and the initiating site was confirmed at the same time. Moreover, the kinetic results indicated the controlled behavior of the graft polymerization, and the composition of the graft copolymer can be regulated by changing the reaction conditions. This work may provide a facile strategy to endow P(VDF-HFP) copolymer with new functions via directly activating C F bonds.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 73
·69580-69585
·
IF 3.289
Xingrong Xiao,Nuoxin Xu,Yongchang Jiang,Qilong Zhang,Enjie Yu,Hui Yang
Ag-loaded TiO2 hybrid particles (TiO2@Ag) were synthesized as fillers by using an ethylene glycol reduction method. Based on this, the TiO2@Ag/P(VDF-HFP) hybrid films were prepared by embedding TiO2 nanoparticles in a poly(vinylidene fluoride-co-hexafluoropropylene) [P(VDF-HFP)] matrix. Morphology and thermal analysis show that the introduction of TiO2@Ag does not disrupt the continuity of the polymer matrix, while the strong interaction between fillers and matrix influences the crystallization process of the composite. The adhesion of Ag to TiO2 efficiently separates the Ag particles from connecting and suppresses the formation of a conductive network, and the ultra-small Ag nanoparticles “trap” the carriers due to coulombic blockade and quantum confinement effect, which results in low dielectric loss and electrical conductivity of the composites. As a consequence, the dielectric permittivity of polymer nanocomposites was enhanced by 300% over the P(VDF-HFP) matrix at a filler content of 30 vol% while maintaining a rather low dielectric loss (0.037 at 1 kHz), demonstrating promising applications in electronic devices.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）