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- A miniemulsion (also known as nanoemulsion) is a special case of emulsion. A miniemulsion is obtained by shearing a mixture comprising two immiscible liquid phases (for example, oil and water), one or more surfactants and, possibly, one or more co-surfactants (typical examples are hexadecane or cetyl alcohol). IUPAC definition Mini-emulsion: emulsion in which the particles of the dispersed phase have diameters in the range from approximately 50 nm to 1 μm. Note 1: Mini-emulsions are usually stabilized against diffusion degradation (Ostwald ripening (ref. )) by a compound insoluble in the continuous phase. Note 2: The dispersed phase contains mixed stabilizers, e.g., an ionic surfactant, such as sodium dodecyl sulfate (n-dodecyl sulfate sodium) and a short aliphatic chain alcohol ("co-surfactant") for colloidal stability, or a water-insoluble compound, such as a hydrocarbon ("co-stabilizer" frequently and improperly called a "co-surfactant") limiting diffusion degradation. Mini-emulsions are usually stable for at least several days. Mini-emulsion polymerization: Polymerization of a mini-emulsion of monomer in which all of the polymerization occurs within preexisting monomer particles without the formation of new particles. There are two general types of methods for preparing miniemulsions: high-energy methods and low-energy methods. For the high-energy methods, the shearing proceeds usually via exposure to high power ultrasound of the mixture or with a high-pressure homogenizer, which are high-shearing processes. For the low-energy methods, the water-in-oil emulsion is usually prepared and then transformed into an oil-in-water miniemulsion by changing either composition or temperature. The water-in-oil emulsion is diluted dropwise with water to an inversion point or gradually cooled to a phase inversion temperature. The emulsion inversion point and phase inversion temperature cause a significant decrease in the interfacial tension between two liquids, thereby generating very tiny oil droplets dispersed in the water. Miniemulsions are kinetically stable but thermodynamically unstable. Oil and water are incompatible in nature, and the interface between them is not favored. Therefore, given a sufficient amount of time, the oil and water in miniemulsions separate again. Various mechanisms such as gravitational separation, flocculation, coalescence, and Ostwald ripening result in instability. In an ideal miniemulsion system, coalescence and Ostwald ripening are suppressed thanks to the presence of the surfactant and co-surfactant. With the addition of surfactants, stable droplets are then obtained, which have typically a size between 50 and 500 nm. Miniemulsions have wide application in the synthesis of nanomaterials and in the pharmaceutical and food industries. For example, miniemulsion-based processes are, therefore, particularly adapted for the generation of nanomaterials. There is a fundamental difference between traditional emulsion polymerisation and a miniemulsion polymerisation. Particle formation in the former is a mixture of micellar and homogeneous nucleation, particles formed via miniemulsion however are mainly formed by droplet nucleation. In the pharmaceutical industry, oil droplets act as tiny containers that carry water-insoluble drugs, and the water provides a mild environment that is compatible with the human body. Moreover, miniemulsions that carry drugs allow the drugs to crystallize in a controlled size with a good dissolution rate. Finally, in the food industry, miniemulsions can not only be loaded with water-insoluble nutrients, such as beta-carotene and curcumin, but also improve the nutrients' digestibility. (en)
- 细乳液是一类特殊乳液。1973年由美国理海大学（Lehigh University）的Ugelstad首先提出。 典型配方为水，单体或单体混和物，乳化剂， （典型为和）和。细乳液聚合一般分为两个阶段: 细乳化阶段和聚合阶段。细乳化阶段主要是通过高剪切力作用，将溶解有乳化剂、共乳化剂的单体分散成直径50—500nm的细液滴。该剪切过程通常经超声或高压均质机来完成。在理想的细乳液过程中，由于乳化剂和共乳化剂的存在，聚并和Ostwald熟化分别被抑制。液滴的尺寸取决于乳化剂和共乳化剂的用量， 以及剪切过程所用的能量。 细乳液过程特别适合于纳米材料和高固含量乳胶的制备。 传统乳液聚合和细乳液聚合的本质区别在于前者是胶束和均相成核， 而后者是液滴成核。细乳液比传统乳液更稳定。 (zh)
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- Mini-emulsion: emulsion in which the particles of the dispersed phase have diameters in the range from approximately 50 nm to 1 μm.
Note 1: Mini-emulsions are usually stabilized against diffusion degradation by a compound insoluble in the continuous phase.
Note 2: The dispersed phase contains mixed stabilizers, e.g., an ionic surfactant, such as sodium dodecyl sulfate and a short aliphatic chain alcohol for colloidal stability, or a water-insoluble compound, such as a hydrocarbon limiting diffusion degradation. Mini-emulsions are usually stable for at least several days.
Mini-emulsion polymerization: Polymerization of a mini-emulsion of monomer in which all of the polymerization occurs within preexisting monomer particles without the formation of new particles. (en)
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- 细乳液是一类特殊乳液。1973年由美国理海大学（Lehigh University）的Ugelstad首先提出。 典型配方为水，单体或单体混和物，乳化剂， （典型为和）和。细乳液聚合一般分为两个阶段: 细乳化阶段和聚合阶段。细乳化阶段主要是通过高剪切力作用，将溶解有乳化剂、共乳化剂的单体分散成直径50—500nm的细液滴。该剪切过程通常经超声或高压均质机来完成。在理想的细乳液过程中，由于乳化剂和共乳化剂的存在，聚并和Ostwald熟化分别被抑制。液滴的尺寸取决于乳化剂和共乳化剂的用量， 以及剪切过程所用的能量。 细乳液过程特别适合于纳米材料和高固含量乳胶的制备。 传统乳液聚合和细乳液聚合的本质区别在于前者是胶束和均相成核， 而后者是液滴成核。细乳液比传统乳液更稳定。 (zh)
- A miniemulsion (also known as nanoemulsion) is a special case of emulsion. A miniemulsion is obtained by shearing a mixture comprising two immiscible liquid phases (for example, oil and water), one or more surfactants and, possibly, one or more co-surfactants (typical examples are hexadecane or cetyl alcohol). IUPAC definition Mini-emulsion: emulsion in which the particles of the dispersed phase have diameters in the range from approximately 50 nm to 1 μm. (en)
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- Miniemulsion (en)
- 细乳液 (zh)
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