Project of Three-Phase Emulsification Technology, Kanagawa University.
J Oleo Sci. 2020 Dec 1;69(12):1551-1560. doi: 10.5650/jos.ess20191. Epub 2020 Nov 12.
The present study investigates the principle difference between three-phase emulsification and conventional emulsification methods (surfactant emulsification and the Pickering method). Conventional emulsification methods depend on intensive factors such as interfacial tension and wetting. In the proposed three-phase emulsification, soft hydrophilic nanoparticles adhere to the oil-water interface due to the van der Waals attraction and stabilize the emulsion. Therefore, it can be said that three-phase emulsification is "extensive emulsification" based on the mass of the hydrophilic nanoparticles and oil droplets. Extensive emulsification is irreversible because the van der Waals attraction acts between the particles unless the mass of the soft hydrophilic nanoparticles and oil droplets changes. The differences between three-phase emulsification and conventional emulsification methods were experimentally verified by comparing the difference in the stability of the emulsions resulting from the change in intensive factors, where the internal phase oil transitioned from solid to liquid. The emulsions prepared using the surfactant and Pickering methods were separated into oil and water by the solid-liquid phase transition of hexadecane in the internal oil phase. However, the emulsion prepared using three-phase emulsification maintained its emulsified state without any oil-water separation even when the internal oil phase underwent solid-liquid phase transition. From the results obtained, it can be concluded that three-phase emulsification is an irreversible method because its mechanism is based on extensive factors. Furthermore, this irreversible method allows the emulsification of various oils that cannot be emulsified by conventional methods, and it is also possible to directly mix emulsions prepared with different oils. The authors also call attention to the possibility of improving emulsion characters and new developments in emulsion science.
本研究探讨了三相乳化与传统乳化方法（表面活性剂乳化和 Pickering 法）之间的主要区别。传统的乳化方法依赖于界面张力和润湿性等强化因素。在提出的三相乳化中，由于范德华吸引力，软亲水纳米粒子附着在油水界面上，并稳定乳液。因此，可以说三相乳化是基于亲水纳米粒子和油滴的质量的“强化乳化”。强化乳化是不可逆的，因为除非软亲水纳米粒子和油滴的质量发生变化，否则范德华吸引力会在粒子之间起作用。通过比较由于强化因素变化导致的乳液稳定性差异，实验验证了三相乳化与传统乳化方法的区别，其中内部相油从固体转变为液体。然而，使用表面活性剂和 Pickering 方法制备的乳液通过内部油相中的十六烷的固-液相变而分离为油相和水相。然而，即使内部油相经历固-液相变，使用三相乳化制备的乳液仍保持乳化状态，没有任何油水分离。从获得的结果可以得出结论，三相乳化是一种不可逆的方法，因为其机制基于强化因素。此外，这种不可逆的方法允许乳化各种不能通过传统方法乳化的油，并且还可以直接混合用不同油制备的乳液。作者还提请注意改善乳液特性和乳液科学新发展的可能性。
