![]() ![]() 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. They can subsequently be broken by low shear or by modifying the particle wettability. Particle-stabilised or Pickering emulsions are versatile systems. 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. Hypothesis: Particle bridges form in Pickering emulsions when the oil-water interfacial area generated by an applied shear is greater than that which can be stabilised by the available particles and the particles have a slight preference for the continuous phase. 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. 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. Shear rheology tests for the aqueous phase and emulsions were performed using a DHR-2 rheometer (TA, USA). Furthermore, the storage stability and rheological properties of Pickering emulsions formulated by RS, OS-RS 3 and OS-RS 20 were investigated. H s and H t were the height of the serum layer and total emulsion. Therefore, OS-RS 20 may provide a novel particle stabilizer for improving the viscoelastic properties and flow behavior of Pickering emulsion. 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. To tackle these problems, herein the ultra-stable linalool/water Pickering emulsions stabilized by -cyclodextrin ( -CD) were successfully prepared through the combination of experiment and molecular dynamics (MD) simulation. The rheological properties indicated that Pickering emulsions formulated by OS-RS 20 displayed better shear stability with shear-thinning behavior as a non-Newtonian fluid. I have been delighted with our results, the ensuring scientific publications and the excellent technical support offered by Analytik Ltd.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). 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. Steve Armes FRS of the University of Sheffield commented:" We purchased an LV1 Microfluidizer because I wanted to conduct fundamental research in the relatively underdeveloped field of Pickering nanoemulsions. Without surfactant (with only LAPONITE as stabilizer) the emulsions are stable to coalescence for several weeks, however they destabilize rapidly under shear. ![]() As pointed by Wei et al., the Pickering emulsion system is a type of power-law fluid that follows Ostwaldde Waele’s relationship. In addition, the combination of high shear mixing with high-pressure microfluidization is applicable to various industrial sectors, such as cosmetics, food manufacturing, drug delivery and agrochemicals. For all Pickering emulsions, the apparent viscosity () gradually decreased with an increase in the shear rate from 0.1 to 10 s 1, indicating the shear-thinning behavior of all emulsions. The LV1 Microfluidizer is ideally suited to this task as it allows researchers convenient access to reproducible high-shear processing, which is essential for the production of relatively uniform Pickering Nanoemulsions. In this particular study, an LV1 Microfluidizer was used to prepare Pickering nanoemulsions using sterically-stabilized diblock copolymer nanoparticles of less than 30 nm diameter. However, the preparation of much finer Pickering nanoemulsions requires further processing via high-pressure microfluidization. Such macro-emulsions are readily prepared simply by high-shear homogenization. It is well-known that micron-sized oil droplets can be stabilised using polymer latex particles of 100-1000 nm diameter. This study examines how subtle differences in nanoparticle emulsifiers affect the long-term stability of Pickering nanoemulsions towards Ostwald ripening. ![]()
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