Conductivity of Sodium Bis(2-ethylhexyl)sulfosuccinate + Isooctane + Water Microemulsions Containing Phase-Transfer Catalysts. 3

Abstract

The effects of temperature and benzo crown ether (BCE) concentration upon the conductivity of the system aerosol OT (AOT) + 2,2,4-trimethylpentane (isooctane) + water have been studied. The BCEs (phasetransfer catalysts) used in the ternary systems were 2,3-benzo-1,4,7,10-tetraoxacyclododec-2-ene (benzo-12-crown-4, BC4), 2,3-benzo-1,4,7,10,13-pentaoxacyclopentadec-2-ene (benzo-15-crown-5, BC5), and 2,3benzo-1,4,7,10,13,16-hexaoxacyclooctadec-2-ene (benzo-18-crown-6, BC6). The behaviors observed were compared with previous ones obtained in the presence of cryptand complexes (CC) and crown ethers (CE) with electrical conductivity.

Effect of Temperature upon Electrical Conductivity of Sodium Bis(2-ethylhexyl) Sulfosuccinate + 2,2,4-Trimethylpentane + Water + Phase Transfer Catalyst

“…Our research group has studied the effect produced upon electrical conductivity behavior by the presence of different PTCs such as cryptand complexes 5 and, crown and benzo crown ethers. 6,7 All cases have shown similar behavior to that observed in this paper. In previous studies in respect to electrical conductivity of water in oil microemulsions, an empirical correlation with three adjustable parameters was developed.…”

“…As we observed for other PTCs, [5][6][7] low additive concentrations hinder the electric percolation phenomena, but medium and high concentrations favor the percolation. At moderate concentrations, they behave similarly to electrolytes.…”

“…Electrical Conductivity Measurements. The experimental procedure has been described in previous papers. − The electrical conductivity ( κ ) was measured with a Crison Conductivimeter GLP 32 conductivity meter with an electrical conductivity cell with a constant of 1 cm -1 . The conductivity meter was calibrated using two KCl conductivity standard solutions supplied by Crison ( C (KCl) = 0.0100 mol·L -1 , κ = 1413 μS·cm -1 at 25 °C and C (KCl) = 0.100 mol·L -1 , κ = 12.88 mS·cm -1 at 25 °C).…”

“…In this work, we carried out studies about the influence of PTC and temperature upon the percolation phenomenon and the use of different equations to fit the experimental data. The results obtained were compared with previous studies that analyzed the effect of the presence of cryptand complexes, crown ethers, and benzo crown ethers upon the electrical conductivity and then upon the percolation phenomena and the value of the percolation temperature.…”

Heat capacity, conductivity, and structural changes of water-sodium dodecylsulfate-triethanolamine-1-pentanol-1,1,2,2-tetrafluorodibromoethane microemulsions

“…In order to obtain additional data on the structure of microemulsions the concentration and temperature dependences of their specific conductivity and specific isobaric heat capacity were determined. The conductivity is most often used to study the structural changes in surfactant micellar solutions and microemulsions [18,19], e.g., to find the critical concentration of surfactant micellization [20], the percolation threshold in w/o type microemulsions [18,[21][22][23][24]. It should be noted that apart from the conductivity, a change in the structure of microemulsions is usually accompanied by an abrupt change in viscosity [17,18,23], some bulk properties, the temperature coefficient of the internal pressure [24][25][26], and optical [27] properties of the microemulsions.…”