Emulsifiers are stabilizers of emulsions and are a class of surfactants. Therefore, after adding an emulsifier to an oil-water system, water and oil can be mixed with each other to form a completely dispersed emulsion. # Requirements for Emulsifiers # A reasonable and qualified emulsifier should meet the following conditions: 1. It has good surface activity in the applied system. That is, the emulsifier can generate lower interfacial tension in the system, can gather on the interface to protect the particles and not remain in any bulk phase (but largely dissolve in any bulk phase), that is, a good hydrophilic-lipophilic balance.
2. It can form a strong adsorption film. That is, a large lateral interaction force can be generated. It is better to understand here that only when a larger interaction force is generated, the protected particles can be prevented from agglomerating and the stability of the system can be improved.
3. The speed of emulsification is faster.
# Classification of emulsifiers # Emulsifiers can be classified according to three aspects: source and state, molecular structure and properties.
1. Source: The main sources of emulsifiers are synthetic (a wide variety and wide range of applications), high polymers (such as natural animal and vegetable gums, polyvinyl alcohol, carboxymethyl cellulose sodium salt, etc.), natural products (such as lecithin, gum arabic, gelatin, lanolin, cholesterol, etc.), solid powder (such as montmorillonite, silica, carbon black, graphite, calcium carbonate, etc.)
2. Molecular structure: Emulsifiers are mainly divided into anionic emulsifiers, cationic emulsifiers and non-ionic emulsifiers from the molecular structure. Among them, non-ionic emulsifiers have developed rapidly because they are not afraid of hard water and are not affected by pH.
3. Properties: Emulsifiers are classified into two types: oil-in-water (O/W) and water-in-oil (W/O).
