HIGH PERFORMANCE POLYMERS
·
2023
·
IF 2.1
Huanhuan Gao,Xiaozhou Zhang,Xigao Jian,Jinyan Wang
In this study, the melt polycondensation reaction of 9,9’- bis(4-hydroxyphenyl)fluoride (BHPF) and diphenyl carbonate (DPC) was catalyzed using three ionic liquids (ILs) and a conventional alkali metal as catalysts. The optimal IL catalysts were determined to be [BMmim][BF4] ionic liquid catalysts, and the catalytic mechanism was investigated. Furthermore, the optimum process conditions were identified: the optimal amount of [BMmim][BF4] was 0.05 mol% based on DPC, the polycondensation temperature was set at 200°C for a duration of 3 h, followed by polymerization at 280°C for another 3 h. As a result, the Mn value of poly(9,9-bis(4-hydroxyphenyl) carbonate) (PFC) reached up to 41387 g/mol with a glass transition temperature band of approximately 254°C and Td-5% value of around 436°C.
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 19
·14631-14636
·
IF 3.84
Haiyan Kang,Xianli Wang,Yan Zhang,Junfeng Wu,Hongqiang Wang
Considering bisphenol A (BPA) and tetrabromobisphenol-A (TBBPA) are ubiquitous environmental pollutants and widely manufactured into packaging materials, foodstuffs may be polluted by BPA and TBBPA. Additionally, there are very limited analytical methods for determining TBBPA in commercial milk samples. In this study, a rapid, simple and efficient method based on microwave-assisted ionic liquid microextraction (MAILME) combined with high-performance liquid chromatography (HPLC) was first applied to the simultaneous analysis of BPA and TBBPA in commercial milk samples. To achieve the optimum extraction performance, the experimental parameters of the MAILME, including type and amount of ionic liquid, microwave power, extraction time, pH and salt concentration in the sample, were evaluated and optimized. Under the optimum conditions, the detection limits were 0.01 and 0.02 μg L−1, and the quantification limits were 0.03 and 0.05 μg L−1 for BPA and TBBPA, respectively. The proposed method had good repeatability and reproducibility with RSDs lower than 5.6%. The recoveries of the analytes in the aged milk samples varied from 79.8 to 97.3%. The proposed method has been applied successfully to the determination of BPA and TBBPA in commercial milk samples with recoveries ranging from 78.2 to 99.8%. Compared with the other previous methods, the proposed method did not need to remove the fats and proteins in the milk, which made the sample pretreatment simple and rapid (5.0 min). And it also avoided the use of organic solvents. The proposed approach provides a new and promising alternative for simultaneously determining trace amounts of BPA and TBBPA in commercial milk samples or other similar samples.
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2015
·
IF 4.321
Suhang Xun,Wenshuai Zhu,Yonghui Chang,Hongping Li,Ming Zhang,Wei Jiang,Dan Zheng,Yuejiao Qin,Huaming Li
A supported SiW 12 O 40 -based ionic liquid (SiW-IL) catalyst with high catalytic activity is designed and synthesized by sol–gel method. The supported catalyst had amphiphilic property, making it exhibit good catalytic performance in solvent-free oxidative desulfurization system. The removal of dibenzothiophene (DBT) with the supported catalyst reached 99.9%, while the sulfur removal is only 6.3% with SiW-IL. The characterizations show that SiW-IL is supported on the carrier successfully and the supported catalyst had a sheet-shaped morphology. Then, various of experimental conditions were taken into consideration to investigate the influences of the desulfurization efficiency and the optimal conditions were obtained. Additionally, sulfur removal of different substrates decreased in the following orders: DBT > 4-MDBT > 4,6-DMDBT > BT under the same conditions. GC–MS analysis was employed to study the mechanism of the desulfurization, DBT sulfone was proved to be the oxidizing product of DBT. Moreover, the supported catalyst had a good thermal and chemical stability, and sulfur removal of DBT still remained 96.2% after recycling 7 times.
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2015
·
IF 2.515
Aiqi Wang,Zhi Zeng,Jinwei Gao,Qianming Wang
An amphiphilic ionic liquid (diallyldimethylammonium tetrafluoroborate) assisted hydrothermal method has been applied for the synthesis of lanthanide fluoride nanoparticles . It has been carried out under mild conditions and large scale amounts of samples can be facilely achieved by this efficient way. Luminescence features of the phosphors were studied by steady state fluorescence and the samples could present striking 5 D 0 → 7 F 1 transition with orange-red color, suggesting that Eu 3 + ions are located in the crystal lattice with inversion symmetry. The particle size distribution was investigated by scanning electron microscope and the results showed that different microstructures such as nano-rods and nanoplates were obtained.
✓ 已验证
DOI
高影响因子
POLYMER
·
2022
·
IF 4.432
Xiaodi Dong,Baoquan Wan,Ming-Sheng Zheng,Haiping Xu,Jiefeng Gao,George Chen,Jun-Wei Zha
There is an urgent need for interlayer dielectric materials with ultralow dielectric properties , high temperature resistance and hydrophobicity in the field of microelectronics due to the development of high-density integration and miniaturization of electronic components. Herein, porous polyimide (PI) films were successfully prepared by using ionic liquid (1-Butyl-3-methylimidazolium tetrafluoroborate, [BMIM][BF 4 ]) as porogen for the first time. Based on the inherent good compatibility between [BMIM][[BF 4 ] and polyimide, this ionic liquid could be uniformly dispersed in the PI matrix, thus creating a favorable prerequisite for the formation of pores. It was demonstrated that the optimized rearrangement of PI molecular chains induced by etching process of [BMIM][BF 4 ] led to the generation of pores and the reduction of chain spacing, which endow the porous films excellent dielectric, thermal and mechanical properties . The film with the porosity ratio of 85 vol% exhibited minimum permittivity of 1.5 at a wide range from 10 2 to 10 6 Hz, high temperature of 5% weight loss about 532 °C. The porous PI films not only provide the promising ultralow permittivity dielectric materials for the development of modern integrated circuits, but also present potential application in adsorption separation and special electromagnetic detection.
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Nan Jin,Jun Yue,Yuchao Zhao,Hongying Lü,Chengxiu Wang
Conventional hydrodesulfurization technology was limited to treat aromatic heterocyclic sulfur compounds in ultralow-sulfur diesel. Extractive desulfurization (EDS) using ionic liquid (IL) exhibited good performance to address these issues, except for its long extraction time (15–40 min). To address this, microreactor was adopted to intensify the IL-based EDS, where dibenzothiophene was extracted from model diesel (MD) as the continuous phase to 1-butyl-3-methylimidazolium tetrafluoroborate as the dispersed phase under segmented flow (which appeared preferably at capillary numbers lower than 0.01). The effects of temperature, residence time and flow rate ratio on the desulfurization efficiency were investigated. The extraction equilibration time could be shortened from more than 15 min in conventional batch extractors to 120 s in microreactors. The extraction process was modeled according to the two-film model applied within a unit cell of the segmented flow, where the mass transfer resistance was considered primarily on the film side of the IL droplet. The mechanism for the improved EDS performance at higher temperatures or larger IL to MD flow ratios was investigated and validated, which was related to the significant increase in the diffusion coefficient or the specific interfacial area. These findings may shed important insights into the precise manipulation of IL-based EDS for a better process design and reactor optimization.
✓ 已验证
DOI
高影响因子
Small
·
2022
·Vol. 18
·期 11
·2106683
·
IF 15.153
Mengyan Cao,Xiujian Zhao,Xiao Gong
Conventional synthesis of carbon dots (CDs) mostly involves a hydrothermal or solvent-thermal reaction which needs relatively high temperature and pressure. In this work, ionic liquid is used to assist in fast synthesizing CDs with an ultrahigh photoluminescent quantum yield (98.5%) by heating at a low temperature (≤100 °C) and at atmospheric pressure. In addition, through this approach, tunable multicolor emissive CDs can be successfully achieved and used for preparing high-performance white light-emitting diodes. Theoretical computation proves that the activity of synthesis reaction can be significantly enhanced by ionic liquids. Density functional theory calculation reveals that the size and graphite nitrogen ratios of CDs have an effect on bandgap reduction, resulting in a redshift of the emission, which is in good agreement with the experimental results. This simple and promising approach for fast synthesis of tunable emissive CDs using ionic liquid affords the facilitation of CDs-based luminescent materials for fast manufacturing of functional devices.
✓ 已验证
DOI
高影响因子
CHINESE SCIENCE BULLETIN
·
2010
·Vol. 55
·期 31
·3562-3568
·
IF 0.917
Yang Wu,He XiaoJing,Gao JinZhang,Guo Hao,He XiaoYan,Wan Fei,Zhao XiuLi,Yu Yan,Pei Ben
Well-defined poly (ionic liquid) brushes with tunable wettability are successfully synthesized via nitroxide-mediated radical polymerization. X-ray photoelectron spectroscopy, attenuated total reflection infrared spectroscopy and static water contact angle measurements are used to monitor each step. Ellipsometry, nuclear magnetic resonance ( 1 H and 13 C) spectra and gel permeation chromatographic measurements reveal that there is a linear increase in polymer film thickness with polymerization time, indicating that chain growth from the surface is a controlled/“living” polymerization. The surface morphology was measured by atomic force microscopy. Moreover, the surfaces of the poly (ionic liquid) brushes with tunable wettability and reversible switching between hydrophilicity and hydrophobicity can be easily achieved by counteranion exchange.
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2020
·
IF 7.246
Wei Zhang,Hairui Ji,Yanliang Song,Sen Ma,Wei Xiong,Changjing Chen,Biqiang Chen,Xu Zhang
To reduce the environment pollution from biolubricant synthesis, in this study, we developed a green and efficient strategy for the preparation of octylated branched biolubricant from waste cooking oil (WCO): (1) WCO was first hydrolyzed by a lipase ( Candida sp. 99–125 ) to produce unsaturated fatty acids (UFAs), the latter was subsequently concentrated by urea complexation; (2) Next, we synthesized new esters using the UFAs as substrate via esterification with 2-ethylhexanol employing lipase (Novozym 435) and the new esters products were further epoxidated; (3) After that, the epoxy group was attacked by a low-cost nucleophilic reagent, octanoic acid, to prepare octylated branched biolubricant using an recyclable ionic liquid , [HMIm][PF 6 ], as catalyst. After three recycling times, [HMIm][PF 6 ] remained catalytic activity with a conversion yield of 81.22% and selectivity of 82.10%. The obtained product showed excellent lubricant properties, such as low pour point of −61 °C, high viscosity index of 149 and high thermal-oxidation stability (onset temperature of 326.35 °C and oxidative onset temperature of 312.06 °C). The high frequency reciprocating rig (HFRR) measurement demonstrated that lubrication performance (friction coefficient of 0.09 and wear spot diameter of 203 μm) was much better than that of mineral based lubricant with the same viscosity grade. Therefore, this study provided a critical synthetic strategy for preparing high-performance biolubricants from WCO.
✓ 已验证
DOI
高影响因子
CRYSTAL GROWTH & DESIGN
·
2021
·
IF 4.076
Yichen Jiang,Zhijiang Wang,Ping Xu,Jianmin Sun
Dicationic ionic liquid 1,1′-(hexane-1,6-diyl)-bis(3-methylimidazolium) dibromide was synthesized inside an MIL-101 metal–organic framework via a facile ship-in-bottle technique. The resultant dicationic ionic liquid @MIL-101 composite contains Cr sites as a Lewis acidic center and Br– as a nucleophile. The high BET surface area (1162 m2/g) and good synergic effects between the dicationic ionic liquid and MIL-101 resulted in good CO2 sorption capacity (47.4 cm3/g at 273 K) and high catalytic activity for the cycloaddition reaction of CO2 with epoxide without any cocatalyst or solvent, and a 92.5% propylene carbonate yield was obtained under 100 °C, 1.0 MPa for 2.5 h. Moreover, the dicationic ionic liquid @MIL-101 composite also showed better recycling stability and easy separation in the CO2 cycloaddition reaction. Compared with the complex synthetic route for the reported ionic liquid functional metal–organic frameworks, the facilely synthesized dicationic ionic liquid @MIL-101 composite exhibited comparable performance in CO2 capture and utilization.
✓ 已验证
DOI
高影响因子
Materials Science & Engineering C-Materials for Biological Applications
·
2017
·
IF 4.164
Hui Mao,Haifeng Zhang,Wei Jiang,Jiachen Liang,Ying Sun,Yu Zhang,Qiuhua Wu,Guolin Zhang,Xi-Ming Song
Poly(ionic liquids) (PILs) have been applied as the linkers between Au nanoparticles (NPs) and polypyrrole nanotubes (PPyNTs) for the synthesis of Au/PILs/PPyNTs hybrids. Due to the presence of PILs, high-density and well-dispersed Au NPs have been deposited on the surface of PILs/PPyNTs by anion-exchange with Au precursor and the in-situ reduction of metal ions. The obtained Au/PILs/PPyNTs hybrids can be used as a good steady electrode material for sensitively and selectively detecting epinephrine (EP). The catalytic oxidation peak currents obtained from differential pulse voltammetry (DPV) increased linearly with increasing EP concentrations in the range of 35–960 μM with a detection limit of 298.9 nM according to the criterion of a signal-to-noise ratio = 3 (S/N = 3), respectively, which showed the excellent electrocatalytic activity towards this significant hormone in human life.
✓ 已验证
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2021
·
IF 8.198
Jian Fang,Zhi-Qiang Wang,Xinjia Wei,Yuan Ma,Honghui Gong,Xue-Qing Gong,Zhenshan Hou
The N-formylation reaction of various amines with CO2 is a promising method to utilize CO2 for the production of high value-added chemicals. Herein, an efficient Ru catalyst system consisting of Ru complex ([PPN][Ru(CO)3Cl3]) and the ionic liquid 1-butyl-3-methylimidazolium hydrogen phosphate ([Bmim]2[HPO4]), has been developed for the N-formylation reaction. Activity evaluation demonstrated that the catalyst system exhibited good to excellent yields of formamides under very mild conditions with the assistance of ionic liquids (ILs). Furthermore, the catalyst system could be reused at least five times with a slight loss of activity in N-formylmorpholine production. Further characterization by 1H nuclear magnetic resonance (NMR), 13C NMR, and density functional theory (DFT) calculations showed that the ILs ([Bmim]2[HPO4]) could facilitate the adsorption of CO2 by a concerted action of both cations and anions of the ILs to form phosphorus carbonate intermediate, thus effectively promoting the reaction. DFT calculations demonstrated that the formation of Ru–H was the first step, and then the CO2 absorbed by [Bmim]2[HPO4] inserted directly into Ru–H by cooperating with the Ru sites to form HCOO– species. After that, formate species dissociated from Ru catalysts and dehydrated to form formamides by the catalytic action of Ru complex and the basic IL.
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）