Determination of the second virial coefficient of the interaction between microemulsion droplets by microcalorimetry

The study proposes a novel method of obtaining the information of second vi rial coefficient of interactions between microemulsion droplets by microcal orimetry. By use of a high sensitivity isothermal titration microcalorimetr y to measure the dilution heat of microemulsions solution, information abou t the second virial coefficient of the interactions between the microemulsi on droplets can be derived with the number density of microemulsion solutio n. The derivation is based on a hard-sphere interaction potential assumptio n. The variance of the derived second virial coefficients was verified by t he percolation behavior of different reverse micelles solutions of dioctyl sulfosuccinate sodium salt in decane with or without solutes.