膜法制备乳状液研究进展

Research progress in membrane emulsification technology

膜法制乳是靠膜两侧的压差使分散相通过微孔膜,以小液滴的形式分散在连续相中而形成乳状液的方法。与转-定体系、高压均化等传统方法相比,该法液滴尺寸均一、节能、剪应力小,可应用于化妆品、食品、医药等领域,其中一些应用已经工业化。液滴从膜孔中形成和分离依赖于各种过程参数(如过膜压差、膜表面连续相的剪切应力)、膜材料和结构。很多实验研究集中在膜乳化过程参数的影响上,膜乳化过程的机理尚需进一步完善。

In the membrane emulsification process, the dispersed phase permeates through the microporous membrane and distributes in continuous phase under the pressure driving force. In comparison with the conventional methods, such as rotor-stator systems and high- pressure homogenizers, the technique is highly attractive due to its simplicity, potentially lower energy demands, resulting narrow droplet-size distributions and lower wall shear stress. The application of membrane emulsification has extended to various fields, such as the cosmetics, pharmacy and food industries, and some applications of this technology are now being commercially realized. Droplet formation and detachment from membrane pores depend on various process parameters (e.g. trans-membrane pressure, shear stress of the continuous phase acting on the membrane surface), membrane material and structure. Many experimental studies focus on the investigations of process parameters. However, the physical mechanisms of droplet formation are still under investigation so as to better elucidate the roles of operation parameters, and finally model the process.