室温离子液体1-烷基-3-甲基咪唑硫酸甲酯的合成及电导率研究

利用硫酸二甲酯分别与N-甲基及N-丁基咪唑在室温下反应,一步合成了离子液体1-甲基-3-甲基咪唑硫酸甲酯和1-丁基-3-甲基咪唑硫酸甲酯,测定了在不同温度下离子液体的电导率.结果表明:随着温度的升高,离子液体的电导率迅速增加;同时电导率与温度的变化关系符合多项式方程和Vogel-Tammann-Fulcher(VTF)方程.     

A note on pressure drop for the cross-flow of power-law liquids and air/power law liquid mixtures past a bundle of circular rods

The steady flow of non-Newtonian polymer solutions on their own and together with air transverse to a bundle of circular rods, has been studied experimentally. In particular, the frictional pressure drop has been measured as a function of non-Newtonian power-law constants, flow rates, voidage of bundles and the input fraction of air over wide ranges of conditions as: power-law flow behaviour index, 0.5 to 1; voidage values of 0.78 and 0.87-0.88; air velocity (superficial), 0.09 to 0.28 m/s and liquid velocity (superficial) 0.018 to 0.5 m/s. While the single phase flow results for power-law liquids are in excellent agreement with an existing equation, the two-phase pressure drop results are also in accordance with the form of the well-known Lockhart-Martinelli correlation. Based on these results, it is suggested that a value of 5-10 for the Reynolds number based on rod diameter marks the limit of the laminar flow in such systems.     

Ionic elastomer blends of zinc salts of maleated natural rubber and carboxylated nitrile rubber: Effect of grafted maleic anhydride

Zinc neutralized maleated natural rubbers (Zn‐MNR) were prepared by solution grafting and neutralization with zinc acetate in one‐step. It was later used for blending with carboxylated nitrile rubber (XNBR) in the composition of 50/50 parts by weight. The effect of grafted anhydride content (1.2, 1.6, 2.0, and 2.5% wt of NR) on the tensile properties of ionic rubber blends (Zn‐MNR/XNBR) was investigated. The tensile strength of the ionic blends was found to be greater than those of pure rubbers. The modulus, tensile, and tear strength of the blends dramatically increased with increasing levels of grafted anhydride. The ionic rubber blends also possessed superior physical properties compared to those of the corresponding nonionic rubber blends (MNR/XNBR). Dynamic mechanical thermal analysis and scanning electron microscopic studies were performed to verify the process of mixing. Fourier transform infrared spectroscopic studies were carried out to characterize the nature of specific intermolecular interactions between Zn‐MNR and XNBR chain segments. The results indicated that the ion‐ion (Zn⁺ ‐COO^?) interactions between Zn‐MNR and XNBR are formed at the interface, which provides the mean of compatibilization in the ionic rubber blends. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Preparation and ionic conductivity of solid polymer electrolyte based on polyacrylonitrile‐polyethylene oxide

The transparent and flexible solid polymer electrolytes (SPEs) were fabricated from polyacrylonitrile‐polyethylene oxide (PAN‐PEO) copolymer which was synthesized by methacrylate‐headed PEO macromonomer and acrylonitrile. The formation of copolymer is confirmed by Fourier‐transform infrared spectroscopy (FTIR) measurements. The ionic conductivity was measured by alternating current (AC) impedance spectroscopy. Ionic conductivity of PAN‐PEO‐LiClO₄ complexes was investigated with various salt concentration, temperatures and molecular weight of PEO (Mn). And the maximum ionic conductivity at room temperature was measured to be 3.54 × 10^?4 S/cm with an [Li⁺]/[EO] mole ratio of about 0.1. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 461–464, 2006     

Electrodeposition Behaviour of Cadmium Telluride from 1-ethyl-3-methylimidazolium Chloride Tetrafluoroborate Ionic Liquid

Voltammetry at a glassy carbon electrode was used to study the electrochemical deposition of Cd–Te from the Lewis basic 1-ethyl-3-methylimidazolium chloride/tetrafluoroborate air-stable room temperature ionic liquid between 80 °C and 140 °C. Deposition of tellurium alone occurs through a four-electron reduction of Te(iv) to Te which could be further reduced to Te(-ii) at a more negative potential. The Cd–Te electrodeposits could be obtained by the underpotential deposition (UPD) of Cd on the deposited Te. The UPD of Cd on Te was, however, limited by a slow charge transfer rate. Samples of Cd–Te electrodeposits were prepared on tungsten and titanium substrates and characterized by energy dispersive spectroscope (EDS), scanning electron microscope (SEM), and X-ray powder diffraction (XRD). The results showed that an excess amount of Cd(ii) was required in order to prepare CdTe codeposits with a Cd/Te atomic ratio approached 1/1. The deposit composition was independent of the deposition potential within the Cd UPD range. Raising the deposition temperature increased the UPD rate of Cd and promoted the formation polycrystalline CdTe.     

离子液体在工业废水治理中的应用

综述了应用离子液体作为溶剂的萃取工艺在治理冶金电镀废水、油田采出水、印染废水和化工制药废水中的应用,其可以高效地、高选择性地除去工业废水中的金属离子、有机染料、有机酚类和其他芳香族化舍物,使水体净化。与使用传统有机溶剂的萃取工艺相比较,该萃取工艺具有萃取效率高、萃取过程中不产生二次污染和可回收利用溶剂等特点,因此该工艺有望被广泛地应用于工业废水的治理。     

羟基铝柱撑膨润土吸附[BMIM]C1离子液体

研究了羟基铝柱撑膨润土对[BMIM]C1离子液体水溶液的吸附性能,考察了吸附温度、吸附时间、膨润土用量、离子液体的浓度、pH值等对离子液体吸附率的影响.结果表明:羟基铝柱撑膨润土对[BMIM]C1溶液具有良好的吸附作用;温度对吸附的影响甚微;达到吸附平衡的时间为2 h;吸附率随着吸附剂用量的增加而增大,且离子液体的浓度越大,吸附率越大;在中性溶液中,离子液体吸附率可达到最大值;离子液体在羟基铝柱撑膨润土上的吸附同时符合Lang-muir和Freundlich吸附等温方程.     

Average cluster sizes and cluster size distributions of superfine nickel particles in light media

Effects of shear rates on average cluster sizes (ACSs) and cluster size distributions (CSDs) in uni- and bi-systems of partly charged superfine nickel particles were investigated by Brownian dynamics, and clustering properties in these systems were compared with those in non-polar systems. The results show that the ACSs in bi-polar systems are larger than those in the non-polar systems. In uni-polar systems the behavior of clustering property differs: at the lower ionic concentration (10%), repulsive force is not strong enough to break clusters, but may greatly weaken them. The clusters are eventually cracked into smaller ones only when concentration of uni-polar charged particles is large enough. In this work, the ionic concentration is 20%. The relationship between ACS and shear rates follows power law in a exponent range of 0.176–0.276. This range is in a good agreement with the range of experimental data, but it is biased towards the lower limit slightly. Foundation item: Projects(50474037, 50874087) supported by the National Natural Science Foundation of China; Project (BK2006078) supported by the Natural Scientific Funds of Jiangsu Province, China     

1-乙基-3-甲基咪唑四氟硼酸盐离子液体结构性质的模拟计算

离子液体以其独特的性质广受关注,被称为"绿色设计者溶剂",人们对其潜在的应用价值做了大量的研究.实验采用HyperChem软件构建了1-乙基-3-甲基咪唑四氟硼酸盐([EMIM][BF4])离子液体分子结构的3D模型,并用PM3法进行预优化,然后应用Gaussian 03w程序分别在RHF/6.31G(d)和BLYP/6-31G(d)计算水平上进行量子化学计算,并经振动频率和强度分析得到理论红外谱图.结果表明,[EMIM][BF4]离子液体的阴阳离子存在着氢键等弱相互作用.     

以离子液体为溶剂制备纤维素微球

将天然纤维素溶于离子液体中,制成纤维素/离子液体溶液,并以纤维素/离子液体溶液为原料采用悬浮聚合法制备了纤维素微球.讨论了纤维素种类和质量分数、纤维素/离子液体溶液与导热油体积比、搅拌速度和制备温度对纤维素微球粒径分布的影响.结果表明,质量分数为2％的棉纤维素/离子液体溶液,以导热油为分散相,V(纤维素/离子液体溶液)...