The term "bubble" or "bubble" refers to the presence of insoluble gases in a liquid or solid, or in bubbles surrounded by their film. Usually to the slurry, dye and other dispersions to add a small amount of a substance, this substance is called "defoaming agent". Any factor that can destroy the stability of foam can be used for defoaming. Defoaming includes two factors: "suppressing bubbles" and "breaking bubbles". Defoaming agents are characterized by strong defoaming power, stable chemical properties, physiological inertia, heat resistance, oxygen resistance, corrosion resistance, gas dissolution, air permeability, easy diffusion, easy penetration, difficult to dissolve in defoaming system, no physical and chemical effects, and less amount of defoaming agent.

So, what is the mechanism of defoaming agent?

1. The electrolyte collapses the surfactant double layer causing bubbles to burst

For the surfactant with the help of foam double electric layer interaction, the stability of foaming liquid, adding ordinary electrolyte can collapse the surfactant double electric layer to play a role in defoaming.

2. Defoaming agent can destroy the elasticity of film and cause bubble burst

When defoaming agent is added to the foam system, it will diffuse to the gas-liquid interface, making it difficult for the surfactant with foam stabilizing function to recover the elasticity of the film.

3. Defoaming agent can cause the liquid film to drain, resulting in bubble burst

The rate of foam drainage can reflect the stability of foam. Adding a substance that accelerates foam drainage can also play a role in defoaming.

4. The addition of hydrophobic solid particles can cause bubbles to burst

Hydrophobic solid particles on the surface of bubbles will attract the hydrophobic end of surfactants, so that hydrophobic particles produce hydrophilicity and enter the water phase, so as to play the role of defoaming.