However, OS-RS 20 with homogeneous distribution of OS groups in the whole particles resulted in the formation of a tighter droplet network structure that was more resistant to external impacts, which showed OS-RS 20 could improve the shear stability of Pickering emulsion.ĭistribution of OS groups Octenyl succinic anhydride modified rice starch Pickering emulsion Shear stability Storage stability.Ĭopyright © 2019 Elsevier Ltd. OS-RS 3 with more hydrophobic groups in the granule surface could form more compact oil/water layers which contributed greater to the storage stability of Pickering emulsion due to the formation of more compact oil/water layers. This work examines how changing the physical state of dispersed phase alters the shear stability and bulk viscoelasticity of o/w emulsions. However, the dispersed phase can be non-Newtonian such as one that can be subjected to a phase change under certain experimental conditions. Advances in clayff molecular simulation of layered and nanoporous materials and. shear thinning was observed, but in the case of the Pickering emulsion. Emulsion index of OS-RS 20 were always lower than OS-RS 3 during the storage time, while G', G" and viscosity of O/W Pickering emulsion formulated by OS-RS 20 particles were greater than those of OS-RS 3. Often, Pickering emulsion studied have a Newtonian dispersed phase. Emulsions stabilized with solid nanoparticles: Pickering emulsions. Our numerical simulation method was based on a phase-field model for capturing a. Furthermore, the storage stability and rheological properties of Pickering emulsions formulated by RS, OS-RS 3 and OS-RS 20 were investigated. The results indicated that 20% of NaOH could destroy the structure of starch more seriously and led to more OS groups travelling to interior of starch granules. This gel formation also accounts for the instability of the emulsions to shear that we observe caused by shear thinning of the continuous gel and inability of the adsorbed particles to rearrange effectively around the droplets due to their attractive nature.The modified rice starches by octenyl succinic anhydride (OS-RSs) with the same degree of substitution of 0.033 were prepared in aqueous solution using 3% or 20% (w/w) NaOH as a catalyst (OS-RS 3 or OS-RS 20). Also, an overview of the various tuneable factors associated with the functionalisation or surface modication of these solid particles, that govern the stability of the Pickering emulsions is provided. Our results suggest that the formation of the emulsions is mostly due to gel formation of the clay particles in the continuous phase, rather than that the clay is an emulsifier. Without surfactant (with only LAPONITE® as stabilizer) the emulsions are stable to coalescence for several weeks, however they destabilize rapidly under shear. 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. We show that the emulsions in the presence of surfactant (with or without clay) are stable to coalescence and shear. The high internal phase emulsion stabilized by solid particles is also called high internal phase Pickering emulsion (HIPPE), and the oil concentration is generally >74 ( 4 ). This allows us to show directly using confocal microscopy, that the clay particles are not only located at the interface but also aggregate and form a gel in the continuous aqueous phase. Pickering emulsions, as solid particle stabilized emulsions, show to have long-term stability and many unique advantages over ordinary emulsions ( 1 3 ). We found that HIPPE with an internal phase volume fraction of 80 can be obtained at 0. In this study, a high internal phase Pickering emulsion (HIPPE) was prepared by centrifuging pre-emulsions at different CNC concentrations. Performance of a polymer flood with shear-thinning fluid in. To clarify the structure of the emulsion and the role of the clay particles, we have succeeded in fluorescently labelling the clay particles by adsorbing the dye onto the particle surfaces. A route for creating edible 3D materials is the use of highly concentrated oil-in-water emulsions. Keywords: Pickering emulsion, mesoporous nanoparticles, enhanced oil recovery. We investigate the role of LAPONITE® particles on high internal phase emulsion stability by considering three different situations: emulsion stabilization by surfactant only, by surfactant plus clay particles, and finally clay particles only. Commonly the stabilization is a combined effect of particle adsorbing at the fluid interface and a particle network in the continuous phase the contribution of each to the overall stability is difficult to assess. Colloidal particles are often used to make Pickering emulsions that are reported to be very stable.
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