How do dispersants work?

A dispersant is a chemical additive used to prevent or inhibit the aggregation of substances. It is widely used in various industrial fields such as paints, inks, plastics and cosmetics. The main function of dispersant is to make solid particles or liquid particles evenly dispersed in the medium through specific action principle, and prevent them from coagulation or precipitation.

I. Definition and function

Dispersants mainly prevent coagulation of particles by reducing interfacial tension so that solid particles or liquid particles can be more evenly distributed in the medium. This helps to improve the stability, fluidity and usability of the product.

Second, the principle of action

The action principle of dispersant mainly includes the following aspects:

1. Electrostatic repulsion: the dispersant can be adsorbed on the surface of the particles, so that the particles produce electrostatic repulsion, thus preventing the particles from approaching and coalescing.

2. Stereotactic resistance: the dispersant forms a film or adsorption layer on the surface of the particles, increasing the spatial resistance between the particles, making it difficult for the particles to get close to each other.

3. Wetting effect: dispersant can reduce the interfacial tension between liquid and solid, so that the solid particles can be easily wetted by the liquid, which can help the dispersion of the particles.

4. Chemical reaction: some dispersants can have chemical reaction with the surface of the particles, changing the nature of the surface of the particles, making it easier to disperse.

Third, the specific application

In paints and printing ink, dispersants help pigments and fillers to disperse evenly, prevent agglomeration and precipitation, and improve the stability and performance of products. In cosmetics, dispersants help to maintain the uniform distribution of various ingredients and improve the use of products. In plastics processing, dispersants help prevent the aggregation of fillers and reinforcing materials and improve the mechanical properties of plastics.

Fourth, precautions

When using dispersants, you need to choose the right type and amount of dispersant according to the specific application scenario. Too much dispersant may cause the system to be too stable, affecting the processing and use of product performance. In addition, attention needs to be paid to the compatibility and stability of the dispersant to ensure its effective role in the medium.

In short, the action principle of dispersant is mainly through electrostatic repulsion, steric site resistance, wetting effect and chemical reaction, etc., so that the solid particles or liquid particles in the medium uniformly dispersed, to prevent their coagulation or precipitation, so as to improve the stability of the product, fluidity and the use of performance.