Tribological Properties of Functionalized Ionic Liquids Containing Ester-group as Lubricants for Steel-Steel System

A series of functionalized ionic liquids （ILs） containing ester-group were synthesized and their tribological prop- erties as lubricants for steel-steel contact were studied and compared with a non-functionalized ionic liquid and perfluo- ropolyethers （PFPE）. The morphology and chemical composition of the worn scars were analyzed by scanning electron mi- croscopy and X-ray photoelectron spectroscopy, respectively, and the possible lubrication mechanism of ILs was discussed. As a result, all ILs demonstrated a better lubricity and a much higher load-carrying capacity than PFPE used as lubricants for the steel-steel tribomates system. The functionalized ILs with ester-group showed slightly worse friction reducing abil- ity than their nonfunctionalized counterparts at relatively lower loads owing to their higher viscosity, but then exhibited better antiwear ability because the ester group they contained had not only physical but also strong chemical reactions with the freshly exposed steel surface and formed chemical adsorption boundary films on the worn surface during friction pro- cess. Under high loads, some triboehemical reactions took place between the active elements, such as fluorine which were released from the ILs, and fresh metal surfaces of rubbing pairs to form the admixture reaction films, which were mainly composed of ferric fluoride mixed with ferric oxide, leading to lower friction coefficients and good wear resistance.

Applications of functionalized ionic liquids

Recent developments of the synthesis and applications of functionalized ionic liquids (including dual-functionalized ionic liquids) have been highlighted in this review. Ionic liquids are at-tracting attention as alternative solvents in green chemistry, but as more functionalized ILs are pre-pared, a greater number of applications in increasingly diverse fields are found.

Finkelstein Reaction in Functionalized Crown-ether Ionic Liquids

Functional crown-ether ionic liquids were used as catalytic green solvents of Finkelstein reaction of 1-bromooctane and iodide. The rate and yield of the reaction were obvious improved compared with that using crown ether in water. No free crown ether loss was observed after reaction.

Catalytic hydrogenation of aromatic nitro compounds by functionalized ionic liquids-stabilized nickel nanoparticles in aqueous phase:The influence of anions

Two kinds of nickel nanoparticles (NPs) well-dispersed in aqueous phase have been conveniently prepared by reducing nickel(II) salt with hydrazine in the presence of amino group (-NH2) functionalized ionic liquids:1-(3-aminopropyl)-2,3-dimethylimidazolium bromide ([AMMIM][Br]) and 1-(3-aminopropyl)-2,3-dimethylimidazolium acetate ([AMMIM][AcO]).The Ni(0) particles are composed of smaller ones which assemble in a blackberry-like shape.The Ni nanoparticles stabilized with [AMMIM][AcO] are much larger than those stabilized with [AMMIM][Br],and the former unexpectedly give much higher activity in the selective hydrogenation of citral and nitrobenzene (NB) in aqueous phase.The Ni(0) nanocatalysts dispersed in aqueous phase are stable enough to be reused at least five times without significant loss of catalytic activity and selectivity during the catalytic recycles.

Synthesis of Fischer indole derivatives using carboxyl-functionalized ionic liquid as an efficient and recyclable catalyst

Fischer indole cyclization of phenylhydrazine and various ketones using carboxyl-functionalized ionic liquid, 1-carboxymethyl- 3-methylimidazolium tetrafluoroborate （abbreviated as [crnmim] [BF4]） as catalyst was successfully performed. The yields of the target compounds were 80-92%, the purities were 96-98%. The catalyst could be recovered and reused for at least six times without significant loss in activity.

Study on Surface Tension and Displacemem efficiency of Ionic Liquid Surfactants Containing Amine Functional Groups

Description is given to preparation of three ionic liquid surfactants containing amine functional groups, characterization of their functional groups using the infrared spectrometer, determination of their surface tension and the oil displacement test in this paper to investigate the effect of alkane branch chains with different carbon numbers on the surface tension and the displacement efficiency. The result shows that, the surfactants exhibit the structural characteristic of the ionic liquid as the characteristic absorption peaks occur on C-N and C-H of the imidazole rings at the wave numbers of 1338cm-1, 1234em-1, 1465crn-1 and 3142cm-1, respectively. The surface tension isothermal curves and the oil displacem ent test proved that the ionic liquid imidazole surfactants with shorter-chain groups are more active on surface, with the minimal surface tension up to 32.5 mN/m, and led to higher displacement efficiency, increasing by 3.3% at the concentration of 1000mg/L compared with the water flooding.

Functional Ionic Liquids Promoted Double Michael Reaction of Benzofuran-3-one or 1-1ndone and Symmetric Dienones： Construction of Spiro[benzofuran-2,1′-cyclohexane]-3-one or Spiro[cyclohexane-1,2′-indene]-1′,4（3′H）-dione Derivatives

The double Michael reactions between benzofuran-3-one or 1-indone and symmetric dienones in the presence of catalytic ionic liquids were successfully developed and spiro[benzofuran-2, 1′-cyclohexane]-3-one or spiro[cyclo- hexane-1,2′-indene]-1′,4（3′H）-dione derivatives containing a spiro quaternary stereogenic center, which widely exist in biologically active products and building blocks in organic synthesis, were obtained in excellent yields （up to 99%）. This catalytic system was also extended to the double Michael reaction of less reactive 1-indone and the desired products were also obtained in 31%-62% yields. The catalytic system was highly active and efficient for a broad of substrates under mild conditions.

Synthesis and Antitumor Activity of Novel Coumarin Deriva- tives via a Three-component Reaction in Water

An efficient synthesis of novel coumarin derivatives via a three-component condensation of 4-hydroxycoumarin, aldehydes and aromatic amines catalyzed by sulfonic acid functionalized ionic liquid L-2-（hydroxymethyl）- 1-（4-sulfobutyl）pyrrolidinium hydrogen sulfate （[HYSBPI]·HSO4） is reported. The condensed product was obtained with excellent yields in water under microwave irradiation condition. The antitumor activities of all the synthesized compounds were assessed on two different human cancer cell lines （A-549 and MCF-7）, and the results showed that these compounds had weak-to-good antitumor activities and their IC50 ranged from 0.05 to more than 100 μmol.L-1.

Epoxy resin nanocomposites reinforced with ionized liquid stabilized carbon nanotubes

Epoxy resin nanocomposites reinforced with three different ionic liquid functionalized carbon nanotubes(f-CNTs)were fabricated by an in situ polymerization method.The influence of the anions on the curing process was studied through differential scanning calorimetry(DSC)and normalized Fourier transform infrared(FTIR)spectroscopy.The composition of the nanocomposites was analyzed by X-ray photoelectron spectroscopy.Two different mechanisms are proposed to explain the curing process of the neat epoxy and its composites.The electric conductivity and mechanical properties of the nanocomposites are also reported.The tensile strength was increased dramatically due to the insertion of f-CNTs.Scanning electron microsopy fracture surface analysis indicates a strong interfacial bonding between the carbon nanotubes and the polymer matrix.