Rheological properties of highly concentrated fluorinated water-in-oil emulsions

Highly Concentrated Emulsions: Role of Droplet Size

“…This means that the elasticity of this emulsion material was determined by the surface of the droplets. This observation was found to contradict the theoretical models proposed by Princen and Kiss (1986), Babak et al (2001), and Pal (2002), where the elastic modulus was expected to depend on the reciprocal diameter. Nevertheless, the observation was quite analogous to the one made and published previously by Malkin et al (2004) and Malkin (2007a, 2008); the last publication was to verify the correctness of this equation (Equation (1)) using D 32 instead of D 50 .…”

The application of a multi-scale approach to the manufacture of concentrated and highly concentrated emulsions

“…In fact, interactions at the molecular scale are only a part of what defines the behavior of emulsions. Analogously, at the macroscopic level, as highlighted by Dimitrova and Leal-Calderon (2004), Babak et al (2001) and more recently by Derkach (2009), several factors affect the behavior of emulsions: the volume fraction of the dispersed phase, the droplet size, the polydispersity of the droplets, the temperature and the emulsification process. This behavior is usually studied using rheological measurements such as steady-state flow experiments to determine the viscosity as a function of the shear rate and thus observing both the shear thinning behavior and the yield stress (Pal, 1999) -and oscillatory experiments in which the elastic and viscous moduli (G and G ) are obtained (Mason et al, 1997;Fa et al, 2004).…”

Highly concentrated emulsions: 1. Average drop size determination by analysis of incoherent polarized steady light transport

“…Some particular emulsions contain a very large amount of dispersed phase, up to 99%. These emulsions, called ''highly concentrated emulsions", ''biliquid foams", ''aphrons" and ''high internal phase emulsions ratio, HIPRE" [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], are defined as containing a volume fraction of dispersed phase larger than volume fraction of 0.74, corresponding to the most compact arrangement of monodisperse hard spheres, reached for a face-centered cubic packing [1]. Beyond u = 0.74, the continuous phase consists in thin liquid films which separate close-packed drops, often distorted as polyhedral cells.…”

“…Beyond u = 0.74, the continuous phase consists in thin liquid films which separate close-packed drops, often distorted as polyhedral cells. In the last years, several studies have been dedicated to understand the relationships between the preparation processes and the formulation with the structure and properties of these particular emulsions [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18].…”