Comparison of micro-DSC and light scattering methods for studying the phase behavior of n -alkane in the oil-in-water dispersion

This article investigates the phase behavior of n-octacosane (C28H58) in the form of an aqueous dispersion with a particle size of about 100 nm. Samples of stable dispersions were prepared by ultrasonication without the addition of surfactants. Studies at various concentrations of n-alkane were performed by differential scanning calorimetry (DSC), powder X-ray diffraction, and light scattering methods. At low n-alkane concentrations, the sensitivity of DSC is not sufficient to detect the paraffin phase transitions. The light scattering method allows determining the phase transition temperatures (melting, crystallization, rotator phases) of n-alkane even in the 10−4 mass% dispersion.