N-甲基-N-苄基吗啉盐酸盐离子液体的合成及性能

采用价格比较低廉的N-甲基吗啉为原料,合成了N-甲基-N-苄基吗啉盐酸盐离子液体.研究结果表明:该离子液体易溶于极性溶剂而难溶于非极性溶剂中;在水中和无水乙醇中的电导率随浓度的增大而增大并且在水中的电导率大于无水乙醇中的电导率;红外光谱分析表明合成的产物与目标产物结构相符;DSC分析表明该离子液体的熔融温度为116℃,低于150℃.属于离子液体范畴.通过对该离子液体的物理、化学性质进行测定,为该离子液体的应用提供依据.     

N-甲基-N-乙基吗啉四氟硼酸盐离子液体的合成及其双水相萃取牛血清蛋白的研究

采用价格廉价的N-甲基吗啉、溴乙烷、四氟硼酸钠为主要原料,通过一锅法,合成了N-甲基-N-乙基四氟硼酸盐吗啉离子液体.通过X射线衍射仪对该离子液体进行了表征,并且测定了其溶解性和电导率等物理性质.结果表明,该化合物结晶度、纯度高,在极性溶剂中具有良好的溶解性,在不同溶剂中的电导率差异很大.将该离子液体应用于牛血清蛋白的萃取,并考察了离子液体浓度及成相盐浓度对萃取率的影响,结果表明在pH值为5.3,离子液体浓度为350g/L,成相盐浓度为80g/L时,牛血清蛋白萃取率达99％以上.     

吗啉离子液体的合成及其在酯化反应中的应用研究

采用一步合成法,以价格低廉的N-甲基吗啉为原料,合成了N-甲基-N苄基吗啉盐酸盐离子液体,并将其应用于乙酸正丁酯合成。通过对醇/酸摩尔比（原料比）、离子液体用量及反应时间的考察,进行正交试验。结果表明酯化反应的最佳条件为酸/醇摩尔比为1：1.5,离子液体用量为0.05g,反应时间为2h,反应温度在110℃左右,酯化率达到50%以上。     

用离子色谱法测定抗生素药物中N-甲基吡咯烷的含量

用离子色谱法成功地取代液相色谱法而建立了测定Cefepime抗生素药物中N-甲基吡咯烷含量的新方法。用DX-120离子色谱仪,以50mmol/L甲基磺酸为流动相,可测定药物中N-甲基吡咯烷的含量。对同一样品分析六次,其峰面积的相对标准偏差小于1.0％。标准曲线的相关系数=0.9996。     

氯化石蜡基支载型离子液体在极压抗磨剂中的应用

通过分子结构设计,将甲基咪唑引入氯化石蜡(CP)分子链中,合成氯化石蜡基支载型离子液体(CP-mimCl),并通过与基础油复配应用于极压抗磨领域。结果表明,热稳定性方面,最大分解温度CP-mimCl提高24℃,最大分解速率降低3.2%/min,并且表现出分解速率较低的特点;极压抗磨性能方面,不同载荷下CP-mimCl复合混合液的平均磨斑直径较CP复合混合液降低6.8%、7.7%、7.3%,摩擦系数降低36.2%,平均p_B值增大15.7%;SEM结果表明,CP-mimCl复合混合液的磨斑形貌较CP复合混合液更为致密和细腻。     

一种新型的液液萃取技术——离子液体萃取

室温离子液体是完全由离子组成的液体。分析中大多数常用的室温离子液体的阳离子是有机基,如咪唑鎓盐、N-烷基吡啶鎓、四烷基铵和四烷基膦鎓离子;阴离子是有机或无机物,如某些卤化物、硝酸盐、乙酸盐、六氟磷酸盐([PF_6])、四氟硼酸盐([BF_4])、三氟甲基磺酸盐和二(三氟甲烷磺酰)亚胺。目前,在分析分离中最常用的室温离子液体是六氟磷酸1-烷基-3-甲基咪唑鎓盐。室温离子液体具有某些独特的物理化学性质:在宽广的温度范围内是液态,只有可忽略的蒸气压,不可燃性,对各种有机化合物和金属离子良好的萃取性能。近几年来,室温离子液体作为一种新型的环境友好的‘绿色'有机溶剂替代传统的挥发性有机溶剂用于痕量离子引起了人们的特别兴趣。它已成功地用于金属螫合物的萃取,是一种有前途的萃取技术。     

离子液体催化合成高粘度指数基础油工艺研究

为制备高黏度指数合成基础油,以1-癸烯为齐聚原料、［Emim］Cl/AlCl3离子液体为催化剂合成聚a-烯烃基础油,考察［Emim］Cl/AlCl3摩尔比、催化剂用量、反应温度、反应时间和原料含水量对反应产物性能及收率的影响。结果表明,提高催化剂AlCl3:［Emim］Cl摩尔比或降低反应温度,合成润滑油的黏度增加;增加催化剂用量可提高产物黏度,但会增加异构化等副反应,降低产物黏度指数;反应原料中含水量变化对聚合度有重要影响,但黏度指数保持稳定。在AlCl3/［Emim］Cl摩尔比为2∶1,催化剂质量分数为10%,反应温度为60 ℃,反应时间4 h的条件下,合成油的100 ℃运动黏度在10.34 mm2/s以上,黏度指数高于143,适合作为柴油机多级润滑油基础油。     

磷酸酯离子液体润滑脂的摩擦学性能研究

用腐蚀性较低、简单易合成的磷酸酯离子液体为基础油,聚四氟乙烯微粉为稠化剂制备一种新型的离子液体润滑脂,在Optimol SRV摩擦试验机上考察其对钢/钢摩擦副的摩擦学性能。结果表明,磷酸酯离子液体润滑脂在室温和高温(100℃)下都表现出优异的减摩抗磨性,并且其减摩抗磨性与离子液体阳离子和阴离子的烷基链长密切相关。磨斑表面扫描电镜和XPS的分析结果表明:摩擦表面既存在离子液体润滑脂与摩擦表面发生摩擦化学反应生成的含有Fe F2、Fe PO4和氮的氧化物的化学反应膜,又存在稠化剂聚四氟乙烯的物理吸附膜。     

耐高温合成酯型离子液体润滑剂的制备及性能研究

以航空发动机基础油季戊四醇多元醇酯(5750)与双三氟甲烷磺酰亚胺锂(Li TFSI)为原料,通过"原位"方法制备一系列合成酯型离子液体;分别对合成酯型离子液体的热稳定性、蒸发损失、摩擦学性能以及抗氧化性能进行测试。结果表明:与季戊四醇多元醇酯相比,合成酯型离子液体具有更优异的热稳定性;当Li与5750的量比为1. 5∶1时,离子液体相比5750基础油起始分解温度可提高33℃,50%分解温度可提高99. 4℃,192 h蒸发损失降低61. 9%;当Li与5750的量比为1∶1时,离子液体的高温摩擦学性能最好,摩擦因数和磨斑直径较5750分别减少32%和56%;合成酯型离子液体对胺抗氧剂表现出更好的感受性。     

两种离子液体的摩擦学行为研究

合成了1-丁基-3-甲基咪唑四氟硼酸盐([Bm im]BF4)及1-羟乙基-3-甲基咪唑四氟硼酸盐([C2OHm im]BF4)2种室温离子液体。在四球摩擦机上研究了这2种离子液体的摩擦学性能,用SEM和XPS对磨痕表面的形貌和元素组成进行了表征,并分析了2种离子液体不同的润滑机制。结果表明,由于[C2OHm im]BF4上的功能化基团容易吸附在摩擦副表面,其在中低载荷下有更好的减摩抗磨性能。     

吗啉的性能及其在金属加工液中的应用

介绍吗啉的性质和用途,提出将吗啉作为一种防腐防锈添加剂应用于金属加工液的设想,并通过试验证明将吗啉应用于金属加工液中可以有效提高其防腐、杀菌、防锈和抗氧化等综合能力.     

烷基咪唑-螯合硼酸离子液体摩擦学性能

以1,3-二癸基咪唑为阳离子,双水杨酸螯合硼酸为阴离子开发一类新型的环境友好螯合硼酸酯-烷基咪唑离子液体n-DICB/i-DICB,采用四球试验机考察2种添加剂在三羟甲基丙烷三油酸酯(PETO)基础中的摩擦学性能,采用SEM、EDX和XANES分析磨损表面的形态和摩擦中形成的摩擦膜的化学成分。结果表明：n-DICB/i-DICB具有优异的综合摩擦学性能,可显著提高可生物降解基础油的减摩、抗磨和极压性能;i-DICB的减摩性能和极压性能优于n-DICB,质量分数2.5%的i-DICB可使PETO的摩擦因数和磨斑直径分别降低33.0%和22.1%,最大无卡咬负荷提高66.6%。摩擦过程中,n-DICB/i-DICB形成了由B₂O₃、Na₂B₄O₇、NaBO₃和BN等混合物组成的致密摩擦膜,这是离子液体具有优异的摩擦性能根本原因。     

Evaluation of Vapor Pressure and Ultra-High Vacuum Tribological Properties of Ionic Liquids

Ionic liquids are a class of salts that incorporate polyatomic anions and cations. These materials are typically viscous fluids at room temperature. The fluids are generally characterized as possessing negligible vapor pressures under ambient conditions. These beneficial properties have led us to study the effectiveness of ionic liquids containing both organic cations and anions for use as lubricants with space applications. This article presents vapor pressure measurements for four ionic liquids as well as friction coefficient data from a spiral orbit tribometer in the boundary lubrication regime under simulated space conditions using stainless steel tribocouples. In addition, we present the first tribological data on mixed ionic liquids and an ionic liquid additive. Postmortem infrared and Raman analyses of the balls and races indicates that the major degradation pathway for these organic ionic liquids is similar to those of other carbon-based liquid lubricants; that is, deterioration of the organic structure into amorphous graphitic carbon. The coefficients of friction and lifetimes of these lubricants are comparable to or better than those of several commonly used space oils.     

Conductive and Tribological Properties of Lithium-Based Ionic Liquids as Grease Base Oil

This article reports several conductive greases prepared by ionic liquids (ILs) that are synthesized by mixing lithium tetrafluoroborate (LiBF₄) or lithium bis(trifluoromethane-sulfonyl) imide (LiNTf₂) in diglyme (G2) and tetraglyme (G4) with appropriate weight ratios at room temperature (RT). The ILs have good solution in poly(ethylene glycol-ran-propylene glycol) monobutyl ether (PAG) and thus can be used as a base oil for preparing grease for steel–steel contacts. The electrical conductive properties of the grease prepared with the mixed oil of PAG plus ILs were evaluated using the DDSJ-308A conductivity tester, GEST-121 volume surface resistance tester, and HLY-200A circuit resistance tester. Combining the free volume with viscosity, the conductivity is inversely proportional to viscosity. The tribological properties were investigated using an MFT-R4000 reciprocating friction and wear tester. The results demonstrated that the prepared greases possess better conductive and tribological properties than the commercial grease with Cu powder as an additive.     

环境友好脂肪酸型离子液体的流变学与摩擦学性能

为研究不同结构脂肪酸离子液体的流变学及其对润滑油性能的影响,以蓖麻油酸、油酸、二聚酸及胆碱为原料,制备3种环境友好型润滑材料([cho][ricinoleat],[cho][oleat],[cho][dimer]),采用流变仪和SRV摩擦试验机研究其流变学和摩擦学性能,采用扫描电子显微镜(SEM)和X-射线能谱仪(EDS)对磨损表面进行分析,初步探讨其润滑机制。结果表明：制备的[cho][ricinoleate]和[cho][dimer]是离子液体,室温下以液体状态存在,而[cho][oleic acid]室温下是以半固体的形态存在,类似润滑脂;随着温度和剪切速率的变化,[cho][ricinoleate]和[cho][dimer]黏度始终大于150BS基础油,其中[cho][dimer]黏度最大,并具有最优的减摩和抗磨性能,其主要原因可以推测为离子液体在金属表面形成双电层结构的吸附膜,以及离子液体较高的黏度增加了油膜厚度以及承载能力。     

Influence of Certain Vapors and Liquids on the Frictional Properties of Molybdenum Disulfide

The influence of certain vapors and liquids on the coefficient of friction of molybdenum disulfide has been studied under boundary conditions. The vapors investigated were those of water, butanol, benzene, and heptane. The liquids used were water, glycol, glycerol, dodecanol, dodecylamine, dodecane, hexadecane, ocladecane, white paraffin oil with and without additions of nonanoic acid and nonyl alcohol, and commercial mineral oil. The tests were performed on various friction testing machines, viz., on the LFW-1, LFW-2, Almen-Wieland, and Reichert machines. The test results show that the coefficient of friction of molybdenum disulfide is lowest in absence of the vapors or liquids studied, and under these conditions is independent of load. With increasing polarity of the vapor or liquid the coefficient of friction of molybdenum disulfide increases.     

不同离子液体润滑条件下BCN薄膜摩擦学性能研究

利用中频磁控溅射技术,分别溅射硼靶和石墨靶,在单晶硅衬底上制备BCN薄膜;采用原子力显微镜(AFM)对薄膜的表面形貌进行分析;在1-正丁基-3-甲基咪唑四氟硼酸盐(L104)和1-正己基-3-乙基咪唑六氟磷酸盐(L-P206)离子液体润滑条件下,利用CSM摩擦磨损试验机考察BCN薄膜/钢球摩擦副的摩擦磨损性能;利用电化学腐蚀方法考察薄膜在离子液中的耐腐蚀性能.实验结果表明:所制备的BCN薄膜均匀、致密,表面粗糙度小;在离子液体润滑剂润滑下,BCN薄膜表现出良好的抗磨减摩性能和抗腐蚀性能;与L-P206离子液润滑剂相比,BCN薄膜在L104离子液体润滑剂润滑下的摩擦学性能更好,这可能与L104离子液体自身的分子结构及其腐蚀性弱有关.     

Biobased Green Lubricants: Physicochemical,Tribological and Toxicological Properties of Fatty Acid Ionic Liquids

Fatty acid ionic liquids (FAILs) were designed and synthesized by combining quaternary ammonium cations with a range of biobased fatty acid anions. They were found to be good and universal lubricants for steel–steel, steel–copper, and steel–aluminum friction pairs, which possess low corrosivities, moderate viscosity indexes, and thermal stabilities compared to commercially available synthetic oil polyalphaolefin (PAO) 10 and traditional ionic liquid (IL) L-F104. Among them, N₁₄₄₄Oct and N₄₄₄₄Oct were found to have far lower toxicity than L-F104. Investigation of the lubricating mechanism revealed that firm and effective physical adsorption and tribochemical reaction films can be easily formed on the sliding surface due to the polarity of the fatty acid anions and the aliphatic tails, which prevent metal–metal contact and further antiwear and reduce friction.