Viscosity and Density of Binary Mixtures of Toluene + Igepal (CO-520, CO-630, CO-720, and CA-720) at T = 293.15–333.15 K and Atmospheric Pressure

Abstract

Surfactants are widely used in industrial applications associated with several solvents. Therefore, it is worthy to know the nature of the molecular interactions present in surfactants and cosurfactant mixtures, whose thermodynamic and physical properties can provide important information from an academic and industrial viewpoint. In this work, density and viscosity data of binary mixtures of toluene + Igepal series (Igepal CO-520, Igepal CO-630, Igepal CO-720, or Igepal CA-720) were experimentally determined within a range of temperature T = 293.15–333.15 K and at an atmospheric pressure of 101.325 kPa. From these data, the following derivative properties have been evaluated: excess molar volume, viscosity deviation, thermal expansion coefficient, partial molar volume, and excess thermal expansion coefficient. It was observed that all these mixtures showed the prevalence of dispersion intermolecular forces.

Effect of Temperature on Density and Viscosity for Methanol (1) + IGEPAL (2) (CO-720, CA-720, and CO-630) at Atmospheric Pressure

“…These data exhibit typical behavior for ordinary liquids, where the density and viscosity decrease with temperature. These results agree with findings reported in the literature for mixtures of ethanol (1) + IGEPAL (2) (CO-520, CO-630, CO-720, and CA-720) and toluene (1) + IGEPAL (2) (CO-520, CO-630, CO-720, and CA-720) . Furthermore, the VFTH equation was fitted to viscosity data, and the parameters of eq are given in Table S1 in the Supporting Information, along with the standard deviation of each data set.…”

“…These results agree with findings reported in the literature for mixtures of ethanol (1) + IGEPAL (2) (CO-520, CO-630, CO-720, and CA-720) 19 and toluene (1) + IGEPAL (2) (CO-520, CO-630, CO-720, and CA-720). 20 Furthermore, the VFTH equation was fitted to viscosity data, and the parameters of eq 1 are given in Table S1 in the Supporting Information, along with the standard deviation of each data set. The viscosity data calculated by the VFTH equation return an absolute average relative deviation of 2.96, 2.97, and 3.00% for methanol + IGEPAL CO-720, methanol + CA-720, and methanol + CO-630, respectively.…”

“…These findings align with similar systems reported in the literature, such as ethanol + IGEPAL mixtures 19 and toluene + IGEPAL mixtures. 20 Linear carbon chains play a crucial role in enhancing the molecular arrangement within the mixtures by reducing steric hindrance effects. 19,21 The negative values of calculated V m E can be attributed to two main factors: (i) cross-association among all IGEPAL and methanol molecules, a result highlighted by the peak deviation near a molar ratio of 1:1; and (ii) the very short alkyl chain in methanol, which can enhance the strength of hydrogen bonds.…”

“…The isobaric thermal expansion coefficients of pure IGEPAL (CO-720, CA-720, and CO-630) and methanol, as well as their mixture, are given in Table 5, and the values agree with those reported in the literature. 13,19,20,28,29 The increase in the temperature can result in a higher internal energy within the mixture. Consequently, the mixture density decreases, leading to an increase in the isobaric thermal expansion coefficient.…”

Tuning the decay time of liquid scintillators

“…An obvious criticism of such method could be the relationship of the viscosity of a solvent with temperature 41 . The literature example of toluene gives a 34 % variation of its viscosity in the range 293 -333 K (thus a 40 °C range).…”