Coating professional dispersant sodium hexametaphosphate

sodium hexametaphosphate is used primarily in dispersion in coatings.
The use of coatings is very extensive, and coatings are needed everywhere in homes, buildings, and industries.

The coating is usually a viscous liquid mainly composed of a resin, oil or emulsion, with or without the addition of pigments, fillers, and many additives, in an organic solvent or water.

The additives in the coating can improve the appearance and performance of the coating, such as: bright brightness, light transmission, mildew proof, uniform dispersion, adhesion and the like. Sodium hexametaphosphate is an important coating additive.

Sodium hexametaphosphate is a viscose after water absorption, which is closely related to the nature of sodium hexametaphosphate. The molecular formula of sodium hexametaphosphate is (NaPO3)6, which belongs to a polymorphic polyphosphate, sodium hexametaphosphate. The anion has a high molecular weight and generally contains up to 30-90 PO3 genes and forms a long chain.

In the coating, due to the addition of water glass and other alkaline substances, an alkaline environment with a pH of 10-10.5 is obtained, that is, the concentration of OH- ions in the coating is large, and the reaction proceeds to the right, which contributes to the further decomposition of H3PO4. Promote the conversion of sodium hexametaphosphate to orthophosphate. Moreover, the phosphate at this time will carry out condensation of a plurality of phosphoric acid functional groups, especially at a high temperature, the molecular group of sodium hexametaphosphate will be condensed, and the molecular group after condensation is combined with the three-dimensional network of bentonite molecular groups in the coating, which is effective The ground plays a role in bonding.

As the content of sodium hexametaphosphate increases, the effect on brushability is more pronounced. When the amount of sodium hexametaphosphate is 2%, the coating is thin, the fluidity is good, but the flow is serious. After the paint is applied, there are obvious flow marks, and the effect is poor. When the content of sodium hexametaphosphate in the paint rises to about 6%. It can saturate the paint, brush light and smooth, and the paint will automatically level without leaving traces after brushing for a period of time, and the viscosity will recover. The dripping of the paint is very low and the paint after painting is in gravity. The underlying shape can be maintained to achieve a balance with drip.