What are the benefits of using alkyl polyglycosides in metal processing?

2018-04-19 10:50:09

The surfactant can change (usually reduce) the interfacial tension of the two phases. It is a kind of amphiphilic compound composed of a hydrophilic group and a lipophilic group. The lipophilic (hydrophobic) group is composed of a hydrocarbon chain, and the hydrophilic group is composed of a hydrophilic group. An oxygen-containing group, such as a hydroxyl group, a carboxyl group, an ether group or the like. Therefore, the nature of the surfactant depends not only on the size and shape of the hydrophobic group, but also on the type of hydrophilic group.

According to the nature of the alkyl polyglycoside ionization and the charge of the active ion after ionization, the surfactant can be classified into four types: nonionic, anionic, cationic and amphoteric. The most widely used metal degreasing agents are nonionic and anionic.

In order to express the hydrophilicity and lipophilic ability of a certain surfactant and the balance of the two forces, a lipophilic hydrophilic balance value H.L.B is often introduced. H.L.B is small, indicating that the surfactant has strong lipophilicity to oily soil, poor water solubility, and is often difficult to rinse; H.L.B value is large, indicating that the surfactant has strong hydrophilicity. Good water solubility, but not conducive to adsorption at the two-phase interface.

For the nonionic surfactant H.L. B balance value between 0 and 20, the ionic surfactant balance value H.L. B is between 1 and 40. The detergent H.L.B as a wetting, permeating and emulsifying agent is preferably between 13 and 15.

In the metal processing industry, surfactants are widely used in metal cleaning, pickling, phosphating and anti-corrosion processes. The use of surfactants in metal processing not only improves work efficiency, reduces costs, but also improves product quality.

Surfactant molecules are composed of a polar hydrophilic group and a non-polar hydrophobic group. Adding a small amount of surfactant to the solvent can significantly reduce the surface tension and change the interface state of the system. Wet, emulsify, disperse, solubilize, foam, defoam, anti-corrosion and other effects. There are two main types of surfactants, ionic and nonionic. A large number of practices have proved that surfactants can improve labor intensity and improve quality in metal surface treatment, which has very important economic value.