Formulation variables influencing the properties and physical stability of green multiple emulsions stabilized with a copolymer

Influence of different electrolytes and oils on the stability of W1/O/W2 double emulsion during storage and in vitro digestion

The aim of this study is to formulate a stable water-in-oil-in-water (W1/O/W2) double emulsion using different types of oils and electrolytes. W1/O was formulated with different electrolyte solutions (W1) dispersed in various oils (O) using polyglycerol polyricinoleate as a stabilizer. External aqueous phase was Tween-80 (W2), and W1/O dispersed in W2 was used. The emulsion containing NaCl or MgCl2 exhibited high encapsulation efficiency (EE) and maintained particle size. Regarding the oil type, the emulsion with MCT oil showed a small droplet size and a high viscosity and EE, presenting a stable droplet distribution in optical observation. The stability of emulsion containing NaCl was maintained during the in vitro digestion experiments. MCT oil, NaCl and MgCl2 have the potential to produce stable double emulsions for storage stability and in vitro digestion studies. The findings would be useful for preparing stable double emulsions used in the food and cosmetic industries.

Study on the formation and stability of polyol-in-oil emulsion

In this study, the influence of polyols, emulsifiers and oils on the formation and stability of polyol-in-oil (P/O) emulsions was investigated. The interfacial tension in P/O systems is much lower than that of water-oil systems, so polyols and oils showed a greater affinity, which was not conducive to the stability of the emulsion system. High compatibility of the emulsifier and the inner and outer phases was the key to the formation of stable emulsions. Using polyethylene glycol 400 (PEG) as polyol phase, mineral oil or squalane as oil phase and cetyl PEG/PPG-10/1 dimethicone (EM 90) as emulsifier, long-term stable P/O emulsions with homogeneous droplets were successfully prepared.

Assessment and Application of Modified Cationic Polyvinyl Alcohol Emulsifiers in Bitumen Emulsions

In this work, a series of emulsifiers were prepared by changing the molar ratio of polyvinyl alcohol (PVA) to the long chain quaternary ammonium salt (A0). The emulsifiers were characterised by FTIR and 1HNMR. The stability of the emulsions was checked and evaluated by determining the phase separation and by UV-Vis spectrophotometry. The emulsion stability increased with increasing emulsifier concentration, which was mainly due to the reduced droplet size and increased viscosity of the emulsions. Stability was also dependent on pH. At pH values between 5 to 3, stability was increased, but at further decreasing pH values, the emulsion became unstable or the emulsion separated. This could be mainly because the excess of positive ions compresses the double electron layer. The experimental results showed that PVA as a macromolecular matrix material has a great application potential for the emulsification process.