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21.
Éadaoin McCourt Dr. Kane Esien Li Zhenyu Dr. Solveig Felton Dr. Peter Nockemann 《Angewandte Chemie (International ed. in English)》2023,62(7):e201809334
Herein, we report on the preparation of liquid dimeric lanthanide(III)-containing compounds. Starting from the design of dimeric solids, we demonstrate that by tuning of anion and cation structures we can lower the melting points below room temperature, whilst maintaining the dimeric structure. Magnetic measurements could establish the spin-spin interactions of the neighboring lanthanide(III) ions in the liquid state at low temperatures, and matched the interactions of the analogous crystalline solid compounds. 相似文献
22.
Dr. Chi Zhang Dr. Meiling Shao Dr. Dongqing Wu Dr. Zhongyi Li Muzhi Zhao Xiangfei Zhang Prof. Bin Zhai Prof. Yunjun Luo Prof. Xiaoyu Li 《Angewandte Chemie (International ed. in English)》2023,62(52):e202314052
Azide compounds are widely used and especially, polymers bearing pendant azide groups are highly desired in numerous fields. However, harsh reaction conditions are always mandatory to achieve full azidation, causing severe side reactions and degradation of the polymers. Herein, we report the design and preparation of two azide ionic liquids (AILs) with azide anion and triethylene glycol (E3)-containing cation, [P444E3][N3] and [MIME3][N3]. Compared with the traditional sodium azide (NaN3) approach, both AILs showed much higher reaction rates and functional-group tolerance. More importantly, they could act as both reagents and solvents for the quantitative azidation of various polymeric precursors under mild conditions. Theoretical simulations suggested that the outstanding performance of AILs originated from the existence of ion pairs during the reaction, and the E3 moieties played a crucial role. Lastly, after the reaction, the AILs could be easily regenerated, presenting a safer, greener, and highly efficient synthesis route for azide polymers. 相似文献
23.
Ionic liquids (ILs) have a wide variety of applications in energy storage and material production. ILs are composed of only cations and anions, without any molecular solvents, and are generally known as “designer liquids (solvents)” because their physicochemical properties can be tuned by the combination of ionic species. In recent several decades, research and development activities of rechargeable batteries have garnered considerable attention because certain groups of ILs exhibit high electrochemical stability and moderate ionic conductivity, rendering them suitable for application in high-voltage batteries. ILs with amide anions are representative electrolytes and are extensively researched by many research groups, including our group. This paper focuses on amide-based ILs as electrolytes for alkali-metal-ion rechargeable batteries, introducing their history, characteristics, and existing challenges to be addressed. 相似文献
24.
利用粗粒化分子动力学模拟研究了电场作用下离子型聚合物复合囊泡形变与破裂的过程.定量分析了囊泡破裂过程中的结构变化,包括囊泡的形变程度、破裂速度、组分分布以及破裂后的结构.研究表明,电场强度较弱时,囊泡表面所吸附的聚电解质首先脱落,囊泡由球形结构转变为椭球结构.随着电场强度增大,离聚物的离子侧基发生重新排布,囊泡表面电荷的有序结构被破坏,导致囊泡的结构无法维持而破裂,囊泡塌缩,分裂形成离聚物团簇,并进一步破裂为小尺寸的离聚物聚集体,均匀分散于溶液中.本文利用分子动力学模拟明确了电场中离子型高分子复合囊泡破裂过程的分子机理,为药物释放技术的优化及发展提供了理论支持. 相似文献
25.
《印度化学会志》2021,98(6):100081
Various metal-containing ionic liquids were used as catalysts for Friedel-Crafts reactions. The reaction of R-X with benzene in the presence of M-IL (M = Fe, Zn, Cd, Cu) along with 1-glycyl-3-methylimidazolium chloride ([Gmim] Cl) ionic liquid, leads to the development of several key intermediates. Among them, metal-iron showed higher catalytic activity without organic solvents. This technique features high yield, a simple product isolation, ILs reusability and reduced waste discharge, thus rendering this catalytic system both effective and natural friendly. 相似文献
26.
以cis,cis-1,3,5-三氨基环己烷·3HBr和均苯四甲酸在室温下通过离子键构筑了具有规整形貌和大尺寸的晶态多孔有机盐CPOS-10, 其具有较好的热稳定性和永久多孔性. 得益于规整形貌及大尺寸单晶, 首次实现了对多孔有机盐单晶各向异性质子导电性能的研究, 并结合晶体结构探索了各向异性质子导电的机理. 结果表明, 水分子浓度对CPOS-10质子电导率的大小具有重要作用, 骨架内水分子浓度高的晶面更易于与极性基团构成氢键网络, 促进质子传导, 利用此网络的质子传导具有更高的质子电导率. 因此, 骨架内水分子的不均匀分布是导致单晶各向异性质子导电的主要原因. 对CPOS-10单晶各向异性质子导电性能的探索可为研究多孔有机盐的质子导电机理提供重要的依据. 相似文献
27.
Developing an effective method for improving the reproducibility of positive temperature coefficient(PTC) effect is of great significance for large-scale application of polymer based PTC composites, owing to its contribution to the security and reliability. Herein, we developed a carbon black(CB)/high density polyethylene(HDPE)/poly(vinylidene fluoride)(PVDF) composite with outstanding PTC reproducibility, by incorporating 1-octyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide([OMIm][NTf_2]) into the composite. After multiple repeated temperature cycles, the PTC performance of as-prepared material keeps almost unchanged and the varition of resistance at room temperature is less than 7%. Our studies revealed that [OMIm][NTf2] contributes to the improvement of PTC reproducibility in two ways:(i)it acts as an efficient plasticizer for refining the co-continuous phase morphology of HDPE/PVDE blends;(ii) it inhibits the crystallization of PVDF through the dilution effect, leading to more overlaps of the volume shrinkage process of HDPE and PVDF melt which results in the decrease of interface gap between HDPE and PVDF. This study demonstrated that ionic liquids as the multifunctional agents have great potential for improving the reproducibility in the application of the binary polymer based PTC composites. 相似文献
28.
Dr. Vinayak Adimule R. G. Revaiah Santosh S. Nandi Adarsha Haramballi Jagadeesha 《Electroanalysis》2021,33(3):579-590
In the present work, Cr doped tellurium dioxide nanostructures (CTO NS)(1 wt %, 6 wt %, 8 wt % and 12 wt %) synthesized by co precipitation method and characterized by CV, UV-Visible, SEM, XRD, XPS spectroscopic analysis. Electron beam deposited thin film of CTO NS having 12 wt % of Cr exhibited EGFET-pH sensitivity of 62.03 mV/pH at 250 °C in buffer solutions of pH 6–12, linearity 0.9345, drift rate of 1.12 mV/h and deviation of 0.01145 as compared with 1 wt %, 6 wt % and 8 wt % of CTO NS. 相似文献
29.
《Journal of Saudi Chemical Society》2021,25(9):101318
A novel cellulose acetate-g-poly (2-acrylamido-2-methylpropane sulfonic acid-co- methyl methacrylate) copolymer was prepared via free radical polymerization for the first time. The chemical structure of the graft copolymer was confirmed using FT-IR, 1H NMR and EDX. The TGA and DSC investigated the thermal changes. Factors affecting the grafting process were studied and various grafting characteristic parameters such as grafting efficiency (%), grafting yield (%) and add-on value (%) were determined. Flexible membranes based on different graft copolymer compositions were fabricated by simple solution casting. Physicochemical properties including ion exchange capability (IEC), water uptake (WU) and proton conductivity (σ) were evaluated. These membranes demonstrated higher IEC, WU and conductivity than the pristine CA. The maximum proton conductivity of the CA-g-poly (2-acrylamido-2-methylpropane sulfonic acid-co- methyl methacrylate) copolymer membrane (68%; Add-on %) was found to be 6.44 × 10−3 S/cm compared with 0.035 × 10−3 S/cm of the pristine CA. Thus, the appropriate graft copolymer composition will allow fine-tuning of the physical characteristics and led to several potential applications, such as polyelectrolyte fuel cells membranes or biodiesel production. 相似文献
30.
Seunghyun Jeong Joon Ho Yoon Pankaj Attri In Tae Kim 《Journal of Saudi Chemical Society》2021,25(5):101227
Over the past few years, polymers shown comprehensive utilization in optical devices, solar cells, sensors, and other such devices. However, the efficiency of these devices remains a problem. We have synthesized new thiophene based, lowband gap polymer, poly(2-heptadecyl-4-vinylthieno[3,4-d] [1,3] selenazole) (PHVTS) and investigated the interactions between the PHVTS and ionic liquids (ILs), in this study. We have used imidazolium- and ammonium-family ILs, and studied the interactions using various spectroscopic techniques such UV–visible, FTIR, and confocal Raman spectroscopies. Additionally, we studied surface morphology of the polymer-IL film. Spectroscopic studies show that both families of ILs can interact with the newly synthesized polymer poly(2-heptadecyl-4-vinylthieno[3,4-d] [1,3] selenazole). However, the imidazolium-family Ionic Liquid-polymer (IL-polymer) mixture films show higher conductivities than ammonium-family IL–polymer mixture films. 相似文献