![]() ![]() The results of this study are relevant for particle-stabilised emulsions and foams in a range of pharmaceutical, food and cosmetic formulations as well as ore flotation. The fundamental importance of this result is that the porous particles (or colloid particle agglomerates) may give an oil-in-water or water-in-oil Pickering emulsion depending on whether they are initially impregnated with oil or water. Similarly, the infusion of the porous supra-particles with water led to a different attachment at the air–water interface compared to the attachment of the same supra-particle when dry. We observed that supra-particles infused with water had different wettability and attachment positions at the oil–water interface compared with the same particles infused with oil. We report for the first time results of an MRI study of supra-particles attached to an air–water or an oil–water interface, which indicated that only the surface layer of the building block particles attaches to the liquid interface while the pore fluid was not displaced by the outer fluid. We characterised the surface morphology and the inner structure of supra-particles by SEM imaging. ![]() This preparation technique allowed limited control over the porosity of the supra-particles by varying the initial concentration of the latex particle suspension, the rate of evaporation and the annealing temperature. We controlled the supra-particle size by varying the initial volume of the latex suspension drop, the latex particle concentration and the drop evaporation temperature. Spherical porous supra-particles were produced above 40 wt% initial concentration of the latex particles in the suspension, which had a rough surface, with a porous and amorphous structure. It was found that the emulsions exhibited a shear thinning with yield stress non-Newtonian rheological behavior and that the flow curves were well. Even at these low particle concentrations (0.9 vol.), the dispersions exhibit a large variation in low shear viscosity with salt concentration, due to the formation of a network. We annealed the dried supra-particles at the polymer's glass transition temperature to fuse partially their latex particle building blocks. The dispersion rheology was measured at the same particle and salt concentrations as in the emulsions. We used a simple method for fabrication of millimetre-sized spherical porous supra-particles from much smaller monodisperse latex microparticles as building blocks by evaporation of a polystyrene sulphate latex suspension on a hot super-hydrophobic surface. Title Stokesian dynamics simulations of interfacial colloidal aggregation under shear. Particle-stabilised or Pickering emulsions are versatile systems. Finally, the importance of using Pickering emulsions to carry out reactions in flow and in multi-step cascade systems is highlighted with various examples to support the benefits of transferring this technology to industrial processes.We prepared model porous composite supra-particles and investigated the effect of the initial infused fluid phase on their attachment at the liquid–fluid interface. Session Emulsions, Foams, and Interfacial Rheology. We find that particle exchange occurs by two routes: firstly, during a period of unbridging and rebridging whose duration can be tuned by varying the wettability of the particles and secondly. A section describing methods for recovering the catalyst is also included, in which various stimuli are discussed. An overview is given regarding the kinds of liquid phases comprising the emulsion system, the different types of solid particle stabilizers (whether they contain catalyst or not) and the catalytic reactions studied. Fig.2 Shear rheological properties of the emulsion sample obtained at. A key aspect of the proposed manufacturing process is the utilization of resins consisting of well-established Pickering emulsions that are stable against shear but also readily flow under low. As the area has advanced rapidly, the intention of this review is to summarize the latest innovations being reported. Fig.1 Appearance of the systems containing 65 water, 35 xylene and 0.5 silica nanoparticles (A) Before shearing (B) and (C) sheared at rotation speeds of 50 r/min, respectively, shearing time: 3 min (D) Pickering emulsion obtained at 24000 r/min is solid-like. In the past 10 years a new application has emerged in the field of catalysis to use them as vehicles to carry out catalytic reactions, allowing a more environmentally friendly process with high conversions and selectivities and important advantages for catalyst recovery. All simulations start from a random mixture of fluids and particles. Particle-stabilised or Pickering emulsions are versatile systems. Snapshots of a 3D Bijel (a) and a Pickering emulsion (b): particles (green). ![]()
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