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Tuvalu What are the UV curing defoamer for paints(1)


Tuvalu Selection of antifoaming agents for different applications:


Stability factors of foam
The direct cause of foam is the presence of surfactant, which reduces the surface tension of the solution. Under the combined effect of this reason and the attenuation mechanism of foam, different foam systems show different stability properties, which are mainly related to the following factors: the surface tension of foaming solution, the surface viscosity of foam, the viscosity of solution, the self-healing effect of surface tension (i.e. Gibbs surface elasticity and Marangoni effect) "The surface double layer repulsion and entropy repulsion forces of liquid membranes, the hydrophobic end structure of surfactants, and the steric hindrance effect are not independent factors, and changes in one factor can cause other factors to also change.". The most important factors affecting the stability of foam are the elasticity of the liquid film and the liquid discharge rate. From this perspective, it can be seen that the main factors affecting the stability of foam are different in different foam systems, and sometimes several factors exist at the same time and work together.
In addition to the above factors, some other factors will also affect the stability of foam, such as the size of foam, the coordination of solute and solvent, temperature, pH value, the evaporation rate of solvent, the impact degree of foam and the adsorption rate of surfactant

Flat coating

Alkyl modified organosiloxane
As mentioned earlier, polyether modified polysiloxanes have some shortcomings; Alkyl modified polysiloxanes have precisely these advantages.
This series of polysiloxane products also belong to the comb structure. The molecular weight of this type of product is relatively small, around 10000, and n+m is about 30-50. The main purpose of modifying with alkyl is to improve thermal stability, compatibility, and unstable foaming, and even to have defoaming functions. However, as the modified alkyl chain increases, its ability to reduce surface tension also decreases

Features: Low viscosity, low defoaming pressure


Recommendation: Mineral oils or mineral oil modified polyethers

Elastic coating

A substance that can reduce the surface tension of water, solution, suspension, etc., prevent the formation of foam, or reduce or eliminate the original foam. [1]
Defoaming agents should have the following properties: ① strong defoaming power and low dosage; ② Adding to the foaming system does not affect the basic properties of the system, i.e. does not react with the defoaming system; ③ Low surface tension; ④ Good balance with the surface; ⑤ Good heat resistance; ⑥ Good diffusion and permeability, high positive spreading coefficient; ⑦ Chemical stability, strong oxidation resistance; ⑧ Good gas solubility and permeability; ⑨ Low solubility in foaming solutions; ⑩ No physiological activity, high safety

Features: High viscosity, high UV curing defoamer pressure



Recommendation: Polyether modified silicone


Surface coating and film covering adhesive

Recommendation: Polyethers, which can effectively prevent surface defects and have a small impact on gloss



Water in Water Colorful

Features: More surfactants, stable foam

Tuvalu Recommendation: Use polyethers or mineral oil to modify polyethers

Precautions for use of paint UV curing defoamer:

Before use, stir thoroughly and mix evenly; Adding the paint while stirring; Before use, it is generally not diluted with water; The dosage should be appropriate. Excessive dosage can cause shrinkage, edge shrinkage, poor brushing performance, and other problems; Too little dosage leads to poor defoaming effect; Add it in two stages, namely, add it in the grinding stage and the paint mixing stage, generally accounting for half of the total amount each time. Use defoaming agents with good foam suppression effect in the grinding stage, and use defoaming agents with good foam breaking effect in the paint mixing stage