Excess thermodynamic properties of binary mixtures containing linear or cyclic carbonates as solvents at the temperatures 298.15 K and 315.15 K

Excess thermodynamic properties of the ethylene carbonate–trifluoroethyl methyl carbonate and propylene carbonate–trifluoroethyl methyl carbonate systems at T= (298.15 or 315.15) K

“…A clear maximum can be observed in the (EC + TFMC) system at x EC = 0.60 with G * E = 296 J · mol −1 , while G * E remains quite constant at about 125 J · mol −1 in the 0.2 x 0.7 mole fractions range for the (PC + TFMC) system. These values are significantly higher than those obtained (7) at the same temperatures for the maxima in (EC + DMC) (8 J · mol −1 ) and (PC + DMC) (4 J · mol −1 ), corresponding to a slightly higher viscosity of TFMC than for DMCs and to the steric effect. This effect arises from the varying size ratios of unlike pairs in the mixtures.…”

“…The slight negative excess viscosity and d values close to zero even at equimolar composition for each mixture of our study, suggest that only weak molecular interactions are likely to operate between the unlike pairs, which are consequently less viscous than the pure components. Taking into account the viscosity results obtained in the mixtures involving DMC, (7) one concludes that no drastic difference can be detected between TFMC and DMC behaviours when added to the cyclic PC or EC molecules.…”

“…Measurements were carried out at T = 298.15 K and T = 313.15 K. The apparatus calibrations are indicated in (7) except that of the dielectric constants. Densities (ρ) were measured by using a digital densimeter Sodev Inc. 03D with a reproducibility of (±2 · 10 −6 ) g · cm −3 , which corresponds to a maximum uncertainty of (±2 · 10 −2 ) cm 3 · mol −1 in molar volume.…”

“…(1)(2)(3) Solution properties and potential electrochemical applications (4)(5)(6) depend not only on the solvating a To whom correspondence should be addressed (E-mail: naejus@univ-tours.fr). b E-mail: damas@univ-tours.fr c E-mail: daniel.lemordant@wanadoo.fr d E-mail: coudert@univ-tours.fr e E-mail: patrick.willmann@cnes.fr (13) or references cited therein; b this work; c from reference (7) power towards the lithium ion but also on the conductivity increase of the mixtures. Dimethyl carbonate (DMC) as additive acts as a good co-solvent for such an application as demonstrated in previous studies (7) where we have reported excess properties of (EC + DMC) and (PC + DMC) at T = (298.15 and 313.15) K. In continuation of our previous studies (7,8) about the thermodynamic properties of binary liquids carbonates, we report in this paper some measurements involving mixtures of 2,2,2-trifluoroethyl methyl carbonate (TFMC) with EC and PC at T = (298.15 or 313.15) K. This new solvent which has been easily obtained in pure state in our laboratory, exhibits interesting characteristics as compared to DMC.…”

“…b E-mail: damas@univ-tours.fr c E-mail: daniel.lemordant@wanadoo.fr d E-mail: coudert@univ-tours.fr e E-mail: patrick.willmann@cnes.fr (13) or references cited therein; b this work; c from reference (7) power towards the lithium ion but also on the conductivity increase of the mixtures. Dimethyl carbonate (DMC) as additive acts as a good co-solvent for such an application as demonstrated in previous studies (7) where we have reported excess properties of (EC + DMC) and (PC + DMC) at T = (298.15 and 313.15) K. In continuation of our previous studies (7,8) about the thermodynamic properties of binary liquids carbonates, we report in this paper some measurements involving mixtures of 2,2,2-trifluoroethyl methyl carbonate (TFMC) with EC and PC at T = (298.15 or 313.15) K. This new solvent which has been easily obtained in pure state in our laboratory, exhibits interesting characteristics as compared to DMC. From the physical properties of TFMC (table 1), which exhibits the same boiling point, a higher dipole moment, a higher dielectric constant, and a lower melting point than those of DMC, it is expected that TFMC should be a better solvent than DMC and could be used instead of DMC.…”