Mechanism of microemulsion formation in systems with low interfacial tension: Occurrence, properties, and behavior of microemulsions

Thermodynamic and Kinetic Pathways to Agitated and Spontaneous Emulsification

“…This scenario is valid if the entire system evolves quasistatically toward equilibrium, and when the free energy of dispersion compensates for the increase of interfacial free energy. In reality, emulsification occurs, largely, under nonequilibrium conditions assisted by the difference of the chemical potentials between the initial and final states. ,, While the chemical potentials are equilibrated, various diffusive, chaotic, and dissipative transports are induced, which lead to the formation of various kinetically stable morphologies. − When oil is dispersed in water, or vice versa, with a surfactant dissolved in one of the phases, emulsification occurs readily − with agitation even when the interfacial tension is positive. The issues of agitated and agitation-less emulsification are highly relevant to bilge water that is transferred to a central oily waste holding tank from the point of generation through sliding-shoe and cavity feed pumps .…”

“…The issues of agitated and agitation-less emulsification are highly relevant to bilge water that is transferred to a central oily waste holding tank from the point of generation through sliding-shoe and cavity feed pumps . As the bilge water is transferred, there are splashes into the tank and sloshing with ship motion that often lead to non-negligible agitation. − The oily water in the bilge also ages with time, where emulsification can proceed, seemingly, in the absence of any external agitation.…”

“…While the above process in an agitated fluid is conceptually appealing, the science of emulsification without an external agitation is quite rich. Without going into an extensive discussion of the vast literature existing on the subject, we point out only a few noted contributions. − Sternling and Scriven suggested that certain Fourier modes of the interface excited by thermal fluctuation could be unstable in conjunction with diffusion across the interface and the Marangoni effects caused by the spatial variation of the concentration of a surfactant. The ensuing instability leads to an interfacial turbulence that is further accentuated by a chemical reaction occurring in one of the phases .…”

“…The ensuing instability leads to an interfacial turbulence that is further accentuated by a chemical reaction occurring in one of the phases . Another predominant viewpoint , is that a surfactant could supersaturate if the bulk phases intermix via mutual diffusion, which would alter the standard chemical potential of the surfactant near the interface, thus prompting the formation of emulsified phases.…”

Preparation of nanoparticles of silver halides, superconductors and magnetic materials using water-in-oil microemulsions as nano-reactors

“…During the past fifteen years, studies on both theoretical and experimental aspects of microemulsions have provided a better understanding of the formation, properties, and phase behavior of microemulsions [7][8][9][10][11][12][13]. Due to their importance in various technological applications such as enhanced oil recovery, pharmaceutics, cosmetics, and nanoparticle synthesis, the structure and structural transitions of microemulsions have been extensively studied using X-ray and light scattering, ultracentrifugation, spin label probes, dielectric relaxation, fluorescence probes, and neutron scattering [14][15][16][17][18][19][20][21][22][23][24][25][26][27].…”