An Investigation of Wettability Alteration of Solid Particles in Emulsion from Intermolecular Forces Point of View

Emulsions are widely utilized in cosmetics, nutritional industries, drilling muds and pharmaceuticalconsumptions. Emulsions are thermodynamically unstable and surfactants or surface-active polymersare usually used in order to contribute to form a kinetically stable system. However, surfactantstabilizedemulsions demonstrate short periods of longevity and may be chemically hazardous in somecertain cases. In this research, particles have been used instead of surfactants, which assemble by theoil-water interface as a densely packed layer form. Then, this layer greatly protects against theflocculation of the droplet and also coalescence by means of electrostatic and steric rather than byremarkably reducing the value of oil-water interfacial tension in which the surfactant agent does. Dualwettability of solid particles is critical factor in order to enhance stability of emulsion, which can beachieved using either low concentration of surfactant or chemical modification of the particle surface.According to the results, it can be concluded that the highest level of emulsions stability will be achievedwhen the electrostatic intermolecular forces between nano particles and charged surfactants orhydrogen bonding between nonionic surfactant and nano particles is at the optimum concentration ofsurfactant. This concept is depicted using zeta potential and particles contact angle.

کلیدواژه ها:

Emulsions ، Surfactant ، Polymers ، Intermolecular Forces ، Wettability