Pyridinium based dicationic ionic liquids as base lubricants or lubricant additives

Abstract A series of eight new dicationic ionic liquids incorporating polyethylene glycol chains linking two N-alkylpyridinium moieties through rings position 2, were synthesized and investigated for their potential use as lubricants or lubricant additives. Alkylsulfate and bis(trifluoromethanesulfonyl)imide [NTf2] were selected as anions. Dicationic ionic liquids containing [NTf2] anion demonstrated good properties as neat lubricants showing low coefficient of friction and wear comparable with the reference lubricant (glycerol). Even more interesting could be their use as friction modifier additives since an important decrease in the coefficient of friction was achieved with a really low concentration of ionic liquid. The thermal analysis of all ionic liquids by thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) is also described.

[1]  M. Kalin,et al.  Pyrrolidinium sulfate and ammonium sulfate ionic liquids as lubricant additives for steel/steel contact lubrication , 2012 .

[2]  M. Jansen,et al.  Research on liquid lubricants for space mechanisms , 2000 .

[3]  Josefa Fernández,et al.  Long-term thermal stability of five imidazolium ionic liquids , 2013 .

[4]  D. Armstrong,et al.  Structure and properties of high stability geminal dicationic ionic liquids. , 2005, Journal of the American Chemical Society.

[5]  Feng Zhou,et al.  High-Temperature Tribological Properties of 2-Substituted Imidazolium Ionic Liquids for Si3N4-Steel Contacts , 2008 .

[6]  S. Stolte,et al.  Toxicity and biodegradability of dicationic ionic liquids , 2014 .

[7]  R. Singer,et al.  Biodegradable pyridinium ionic liquids: design, synthesis and evaluation , 2009 .

[8]  Chengfeng Ye,et al.  Polyethylene glycol functionalized dicationic ionic liquids with alkyl or polyfluoroalkyl substituents as high temperature lubricants , 2006 .

[9]  M. Kalin,et al.  Miscibility and tribological investigations of ionic liquids in biodegradable esters , 2014 .

[10]  A. Schwabacher,et al.  DESYMMETRIZATION REACTIONS : EFFICIENT PREPARATION OF UNSYMMETRICALLY SUBSTITUTED LINKER MOLECULES , 1998 .

[11]  María-Dolores Bermúdez,et al.  Ionic Liquids as Advanced Lubricant Fluids , 2009, Molecules.

[12]  W. Binder,et al.  Ethylene glycol‐based ionic liquids via azide/alkyne click chemistry , 2013 .

[13]  Maria Forsyth,et al.  A Review of Ionic Liquid Lubricants , 2013 .

[14]  Peter Wasserscheid,et al.  Ionic Liquids in Synthesis , 2002 .

[15]  Zhuo Zeng,et al.  Polyfluoroalkyl, Polyethylene Glycol, 1,4-Bismethylenebenzene, or 1,4-Bismethylene-2,3,5,6-Tetrafluorobenzene Bridged Functionalized Dicationic Ionic Liquids: Synthesis and Properties as High Temperature Lubricants , 2008 .

[16]  N. Dörr,et al.  Dicationic ionic liquids as lubricants , 2012 .

[17]  Eberhard Schlücker,et al.  Ionic Liquids as Alternative Lubricants for Special Applications , 2010 .

[18]  Bharat Bhushan,et al.  A Review of Ionic Liquids for Green Molecular Lubrication in Nanotechnology , 2010 .

[19]  Joan F. Brennecke,et al.  Thermophysical Properties of Imidazolium-Based Ionic Liquids , 2004 .

[20]  Ichiro Minami,et al.  Effect and mechanism of additives for ionic liquids as new lubricants , 2007 .

[21]  R. Isaksson,et al.  Chiral biphenyl bis(crown ethers): synthesis and resolution , 1987 .

[22]  N. Dörr,et al.  Tribological investigations of ionic liquids in ultra‐high vacuum environment , 2014 .

[23]  Laigui Yu,et al.  Room-temperature ionic liquids: a novel versatile lubricant. , 2001, Chemical communications.

[24]  R. Singer,et al.  The design and synthesis of biodegradable pyridinium ionic liquids , 2008 .

[25]  E. González,et al.  Synthesis and characterization of new polysubstituted pyridinium-based ionic liquids: application as solvents on desulfurization of fuel oils , 2011 .

[26]  M. Kalin,et al.  How anion and cation species influence the tribology of a green lubricant based on ionic liquids , 2012 .

[27]  Ichiro Minami,et al.  Ionic Liquids in Tribology , 2009, Molecules.

[28]  Vladimir Pejaković,et al.  Influence of temperature on tribological behaviour of ionic liquids as lubricants and lubricant additives , 2014 .

[29]  E. Kaiser,et al.  Selective metalations of methylated pyridines and quinolines. Condensation reactions , 1973 .