Search

Pickering emulsion is widely used in food, drug administration, and cosmetics. In practical applications, surfactants are often co-present with particles, so it is particularly critical to study particle-surfactant interactions. Pickering emulsions were prepared using stearyltrimethylammoniumchloride organic montmorillonite (STAC/MMT) and fatty alcohol polyoxyethylene ether (AEO-3) as stabilizers. Effects of AEO-3 content, STAC/MMT content, oil-water ratio, emulsification temperature, emulsification time on emulsion stability were systematically revealed by studying the particle size distribution and phase volume of the emulsion. The formulation of emulsion was optimized by orthogonal experiment and the mechanism of this emulsion system was proposed. The results indicated that the oil-water volume ratio was closely related to the type of emulsification, and when STAC/MMT and AEO-3 were used together, stable W/O emulsions were obtained owing to the synergistic interaction. The orthogonal experiments showed that the emulsion had good static and thermal stability when the STAC/MMT content was 2.0%, the oil-water volume ratio was 1:1, AEO-3 content was 0.25% and emulsification time was 5 minutes. The stability mechanism of this Pickering emulsion was that AEO-3 was used to improve the surface properties of STAC/MMT particles and enhance their emulsifying capacity. The picture shows the interaction between STAC/MMT and AEO-3 in Pickering emulsions. The adsorption of surfactant on particles surface to change its wettability, and at the same time, some surfactants also reduce the interfacial tension by adsorbed at the oil-water interface. [ABSTRACT FROM AUTHOR]

High-amine-value aminopropyl polysiloxanes (APSO) were designed and synthesized via two different methods. APSO was then aminated with glucono-δ-lactone (GL) to produce sugar-modified amodimethicone (GLAP). The properties of GLAP were investigated systematically. GLAP has a low critical aggregation concentration (CAC) and displays low surface tensions at CAC (γCAC). GLAP forms spherical aggregates in solution. Formation of micelles and adsorption at the air-water interface are spontaneous. Moreover, its good solubility and excellent wetting properties make GLAP a potential candidate for application in paints, coatings, and agricultural adjuvants. [ABSTRACT FROM AUTHOR]

To investigate the effect of content of polyether (F400) grafted on the properties of polysiloxane amphiphiles, polyether was grafted on the polysiloxane by hydrosilylation reaction with H2PtCl6 catalyst. The modified polysiloxanes were divided into two types; moreover, the ratio of polyether and polysiloxane was 1:1 or 1:2. The first one was similar to the conventional surfactant structure that is BA polysiloxane amphiphile, which own one hydrophobic chain and one hydrophilic group. Another one was ABA polysiloxane amphiphile, which possess one hydrophobic chain and two hydrophilic groups at the terminal. In our work, we compared the property of modified polysiloxanes with various contents of polyether in aqueous solution at room temperature to analyze the impact of polyether content on siloxane surfactants. The conclusion was that siloxane amphiphiles possess good solubility, high surface activity, and excellent spreading property. [ABSTRACT FROM AUTHOR]