The Property of Silicone Defoamer

The silicone oil-based defoamer is insoluble in water and mineral oil, so its antifoaming ability is strong as well as its antifoaming effect is greatly enhanced. Because Si-O bond and Si-C bond are relatively stable, and they are allowed to be used in systems containing a small amount of acid, alkali and salt. Most of the commonly used silicone defoamers in industrial production are a kind of secondary processing product of silicone oil made by adding dispersants to silicone oil, which are all liquid mixtures.


The antifoaming active ingredient of silicone defoamer is silicon paste. Hydrophobic silica particles in silicone paste can form a defoaming agent dispersion with silicone oil, help silicone oil droplets insert into the surface of foam film, reduce insertion resistance of silicone oil drops and foam drainage time, increase the depth of foam dispersant inserted on the surface of foam film, improve the ability to destroy the oil-water-air film, and accelerate the defoaming speed.


Under the heating conditions, the SI-OH bond in methyl MQ silicone resin can react with the residual Si-Oh in dimethyl silicone oil and hydrophobic fumed silica to form an organic polymer with a complex polymer chain structure. This polymer can effectively improve the dispersibility of silica, and further enhance the synergistic defoaming and antifoaming performance of silica and dimethyl silicone oil.


Emulsion type silicone defoamer uses two methyl silicone oil as the main raw materials, which is a defoamer emulsified by adding methyl MQ silicone resin and hydrophobic carbon black. It can be widely used in food, paper, leather, environmental management, and other aspects of chemical production.

Silicone defoamer is suitable for industrial circulating water, water treatment, circuit board cleaning, metal cutting fluid, metal cleaning, oil processing grinding fluid, and alkaline cleaning fluid. Also, it is suitable for defoaming of textile, printing and dyeing, emulsion polymerization, civil washing, various kinds of colorants and coatings.


Features of silicone defoamer

1. Strong defoaming ability, and it can get a good defoaming effect by adding systematic mass fraction (1×10-6100×10-6).

2. In terms of chemical properties, it’s inert to common substances and will not react chemically with foaming substances.

3. Silicone defoamer has good heat resistance, high and low-temperature resistance. The viscosity of silicone oil increases gradually only when the temperature reaches above 200℃, but its silicon-oxygen bond does not decompose.

4. Good flexibility and lubricity of silicone oil are beneficial to improve the quality of the coated paper.

5. Silicone defoamer is non-toxic, pollution-free, physiological inert and environmentally friendly.

6. Silicone defoamer has outstanding weatherability, durability and aging resistance, and can play its role in any environmental condition.


XJY Silicones

XJY Silicones can provide XJY-8205 MQ resin that can be applied in the silicone defoamer.






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Methyl MQ Silicone Resin


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XJY Silicones as one of the leading silicone manufacturers is a new enterprise for silicone resin innovation and R&D, with more than 30 years of experience in the silicone industry. Our manufacturing, R&D, and sales services had obtained the ISO9001 certificate.