Market research shows that the molecular structure of surfactant is amphiphilic: one end is a hydrophilic group and the other end is a hydrophobic group; the hydrophilic group is often polar Groups, such as carboxylic acid, sulfonic acid, sulfuric acid, amino or amine groups and their salts, can also be hydroxyl, amide groups, ether bonds, etc.; while hydrophobic groups are often non-polar hydrocarbon chains, such as more than 8 carbon atoms hydrocarbon chain. Surfactants are divided into ionic surfactants and nonionic surfactants.
There are many ways to classify surfactants. They are classified according to the hydrophobic structure and are divided into straight chain, branched chain and aromatic Surfactant aroma chain, fluorine-containing long chain, etc.; are classified according to the hydrophilic group and are divided into carboxylates, sulfates, quaternary ammonium salts, PEO derivatives, lactones, etc.; some researchers base their molecular The ionic properties of the composition are divided into ionic, non-ionic, etc., and there are various classification methods based on their water solubility, chemical structural characteristics, raw material sources, etc.
People generally think that it is more appropriate to classify it according to its chemical structure. That is, when surfactants are dissolved in water, they are divided into ionic surfactants and nonionic surfactants according to whether ions are generated and their electrical properties. Classification according to the dissociation properties of polar groups:
1.Anionic surfactant : stearic acid, sodium dodecylbenzene sulfonate
2. Cationic surfactant: quaternary ammonium compound
3. Zwitterionic surfactant: lecithin, amino acid type, betaine type
4. Non-ionic surface Active agent: Fatty acid glyceride, fatty acid sorbitan (Span), polysorbate (Tween)
The application and function of surfactants: Surfactants have lubricating properties Wetting or anti-sticking, emulsification or demulsification, foaming or defoaming, as well as a series of physical and chemical effects and corresponding practical applications such as solubilization, dispersion, washing, antisepsis, and antistatic, have become a flexible and versatile fine chemical industry with a wide range of uses. product.
In addition to being used as detergents in daily life, surfactants have other applications Can cover almost all fine chemical fields.
Surface active agent function:
1. Solubilization;
2. Emulsification;
3. Wetting effect ;
4. Supporting effect ;
5. Foaming and Defoaming effect;
6. Disinfection and sterilization ;
7. Descaling and cleaning effects.