Question:dispersantIs it just a surfactant?
Answer:Is a dispersant a surfactant? Generally speaking, dispersants are a type of surfactant. In other words, dispersants are usually surfactants, but surfactants have many different functions and structures, such as emulsifiers, wetting agents, penetrating agents, solubilizers, and so on.
Surfactant is a chemical drug that can greatly reduce the surface tension of solvents (usually water) or liquid-liquid interface surface tension, change the surface state of the system, and thus achieve a series of effects such as long-lasting wetting and anti wetting, emulsification and demulsification, dispersion and coagulation, foaming and defoaming, and solubilization. The special function played by surfactants is called surface activity.
Dispersant is a chemical agent that promotes the uniform dispersion of material particles in a medium, forming a stable suspension. Dispersants are generally divided into two categories: inorganic dispersants and organic dispersants. Common inorganic dispersants include silicates (such as water glass) and alkali metal phosphates (such as sodium tripolyphosphate, sodium hexametaphosphate, and sodium pyrophosphate). Organic dispersants include triethylhexyl phosphate, sodium dodecyl sulfate, methyl pentanol, cellulose derivatives, polyacrylamide, guar gum, fatty acid polyethylene glycol ester, etc. It can also be said that dispersants are additives that can improve and enhance the dispersibility of solid or liquid materials. When grinding solid dyes, adding dispersants helps to pulverize the particles and prevent them from coalescing, thus maintaining the stability of the dispersion. Oil liquids that are insoluble in water can disperse into very small droplets under high shear force stirring. After stopping stirring, they quickly separate under the action of interfacial tension. However, after adding a dispersant and stirring, a stable emulsion can be formed. Its main function is to reduce the interfacial tension between liquid-liquid and solid-liquid. Therefore, dispersants can also be considered surfactants, but it does not mean that dispersants are surfactants.
Dispersants and surfactants are classifications of compounds from different perspectives. Some surfactants have dispersing functions, but not all. Dispersants can be surfactants, polymers, or inorganic; The two cannot be equated, and there is no question of who includes whom.
