Influence of cationic moieties on the tribolayer constitution shown for bis(trifluoromethylsulfonyl)imide based ionic liquids studied by X-ray photoelectron spectroscopy

Gabler, Christoph; Dörr, Nicole; Allmaier, Günter

doi:10.1016/j.triboint.2014.06.018

Cited by 27 publications

(22 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In fact, micro-Raman confocal and X-ray Photoelectron Spectrometry (XPS) analyses revealed the presence of TiF3 and TiOF2 on worn titanium surfaces lubricated with IL2 and other ILs with fluorinated anions [9,26,44]. Strong correlation can be observed for m/z 2, 17 and 18, which supports the hypothesis of the common precursors and mechanisms of the H 2 and H 2 O emissions.…”

Section: Figuresupporting

confidence: 61%

Section: Figurementioning

confidence: 99%

“…Room-temperature ionic liquids (ILs) are salt structures consisting of large cation and anion moieties, which are characterized by melting temperatures below 100 • C. In tribological applications, ILs have demonstrated superior performance as lubricants under both mixed and boundary conditions [1][2][3][4][5][6][7][8][9]. In severe environments, in space and at high temperatures, IL-base lubricants are especially propitious due to their exceptional thermal stability, both oxidative and nonoxidative [10][11][12][13][14].…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Time-Resolved Characterization of Dynamic Tribochemical Processes for Dicationic Imidazolium Ionic Liquid

et al. 2017

View full text Add to dashboard Cite

Dynamic tribochemical processes for dicationic ionic liquid containing a geminal imidazolium cation head group bridged by a poly(ethylene glycol) and a bis(trifluoromethylsulfonyl)imide anion were studied using time-resolved mechanically stimulated gas emission mass-spectrometry (MSGE-MS). In comparison with similar monocationic imidazolium ionic liquids with short alkyl or long polyether side chains, the dicationic ionic liquid had a lower coefficient of friction on Ti6Al4V alloy and smoother behavior. The analysis of volatile decomposition products suggested multiple tribochemical reactions in which both anionic and cationic moieties are involved. The tribochemical degradation of cations was mainly through the detachment of the side and bridging chains from the imidazolium head groups. The absence of volatile products containing nitrogen implies that the imidazole group remained unchanged. Hydrogen and water desorption were attributed to the reactions of hydrogen fluoride being a product of anion degradation with titanium and titanium oxide, respectively.

show abstract

Section: Figuresupporting

confidence: 61%

Section: Figurementioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Time-Resolved Characterization of Dynamic Tribochemical Processes for Dicationic Imidazolium Ionic Liquid

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Despite their good tribological behaviour, the hydrolysis products of those anions are highly corrosive [36]. This fact provoked the introduction of new and more stable ILs based on [FAP] and [NTf 2 ] anions [37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53], which present enhanced tribological properties due to the formation of fluoride tribofilms, especially at high loads [54]. Recently, phosphonium cation-based ILs have been introduced in this field because of their growing commercial availability and good tribological performance [26,[55][56][57][58][59][60][61][62].…”

Section: Introductionmentioning

confidence: 99%

Isoconversional kinetic analysis applied to five phosphonium cation-based ionic liquids

et al. 2017

View full text Add to dashboard Cite

Thermal degradation of five phosphonium cation-based ionic liquids ([P 66614 outperforming the other ones in both pyrolytic and oxidising conditions. Although the thermal degradation mechanism is affected by atmospheric conditions, the degradation trend remains practically constant. As the dynamic methodology usually overestimates the long-term thermal stability, an isoconversional methodology is better for predicting the long-term thermal stability of these ionic liquids in order to be used as base oil or additive in lubricants formulation. Finally, the model-free methodology can predict at lower costs the ILs performance in isothermal conditions. Highlights• Weakly coordinating anions provoke good thermal stability of ILs.• • Isoconversional methods are better than dynamic ones for long-term thermal studies.• Activation energy behavior at low conversions is related to a single reaction.• Model-free methodology can predict the ILs performance in isothermal conditions.

show abstract

“…The chemical structures of the ILs used in this study are presented in Figure 1. The [BMIM] + and [P 6,6,6,14 ] + cations and the [TFSI] anion have been chosen due to their stable properties in air and under shear [18,[33][34][35][36][37]. As [BMIM] + has more localized charges and shorter alkyl chains than [P 6,6,6,14 ] + , the effect of the chemical structure of the cation on grease rheology is revealed.…”

Section: Introductionmentioning

confidence: 99%

Ionic Liquids as Grease Base Liquids

Mozes

Cooper

2017

Lubricants

View full text Add to dashboard Cite

Abstract:The rheological characteristics of one mineral oil and two ionic liquid (IL) based lubricating greases were explored as a function of thickener concentration. The ILs used are 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([BMIM][TFSI]) and trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl)imide ([P 6,6,6,14 ][TFSI]), with polytetrafluoroethylene (PTFE) particles used as thickeners. Greases with different base liquid concentrations (60-80 wt %) were investigated using small-amplitude oscillatory shear and viscous flow measurements, and contact angle measurements probed adhesion at base liquid-PTFE interfaces. Rheological properties are influenced by base liquid-PTFE adhesion and the chemical structure of the grease base liquids. With the addition of thickener, the greases generally have higher elasticity, strain resistance, and frequency independent properties. Viscometric rheological tests illustrate non-Newtonian shear-thinning behaviour for all greases. [BMIM][TFSI] based greases show the most elastic properties and strain resistance, as well as the highest initial and lowest final viscosities of the greases tested.

show abstract

Influence of cationic moieties on the tribolayer constitution shown for bis(trifluoromethylsulfonyl)imide based ionic liquids studied by X-ray photoelectron spectroscopy

Cited by 27 publications

References 38 publications

Time-Resolved Characterization of Dynamic Tribochemical Processes for Dicationic Imidazolium Ionic Liquid

Time-Resolved Characterization of Dynamic Tribochemical Processes for Dicationic Imidazolium Ionic Liquid

Isoconversional kinetic analysis applied to five phosphonium cation-based ionic liquids

Ionic Liquids as Grease Base Liquids

Contact Info

Product

Resources

About