1-alkylimidazolium tetrafluoroborate

Liu, W. W., X. B. Yan, J. W. Lang, and Q. J. Xue. 2011. Electrochemical behavior of graphene nanosheets in alkylimidazolium tetrafluoroborate ionic liquid electrolytes Influences of organic solvents and the alkyl chains. Journal of Materials Chemistry 21 13205-13212. 

For example, Seddon et al have shown that alkylimidazolium tetrafluoroborate family (number of carbon atoms typically 12) are thixotropic fluids whose viscosity decreases when increasing the shear rate. Kulkami et al have reported that the flow behavior may change from Newtonian to non-Newtonian by inereasing the alkyl chain length on the eat-ion like alkyl-methylimidazolium-based ionie liquids. Non-Newtonian shear thinning behaviors have been then reported for different aprotic or protic ionic liquids. 

Ionic liquids are a good example of the industrial chemicals of the future. They consist of an organic cation, such as alkylimidazolium, alkylpyridinium, alkylphosphonium or alkylammonium, and an organic or inorganic anion, such as tetrafluoroborate, hexafluorophosphate, tosylate or bis(trifluoro-methylsulfonyl)imide. Table 1 presents some common examples of ionic... 

Additionally, ionic liquids are generally described in the literature as Newtonian fluids, in other words, their viscosities remain constant with increasing shear rates. For example, Newtonian behaviors for alkylimidazolium (wifli die alkyl chain length between 1 and 8 carbon atoms) based ionic liquids with tetrafluoroborate, hexafluorophosphate, and bis(trifluoromethylsulfonyl)imide anions are reported in the literature. Nevertheless, this rheological behavior is strongly affected by the choice of ions constituting the ionie liquid. In fact, non-Newtonian behavior has been described for several ionic liquids. 

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