Silicone defoamer is a commonly used chemical substance that is widely used in various fields. Its main role is to reduce or eliminate the formation of bubbles in the liquid, thereby improving the stability and quality of the liquid. Below is a small series to talk about the application of silicone defoamer.
A textile printing and dyeing

01 Sizing process: water-emulsion silicone defoamer, such as: silicone polyether, add 0.2-0.25g /L in the sizing tank


02 Chemical fiber oil agent: chemical fiber oil agent added 0.02¬0.04% water emulsion type defoamer. Organic silicone oil should be included in the formula of chemical fiber oil.


03 Desizing refining: selection of polyether silicone.


04 Bleaching: Strong acid, silicone defoamer.


05 Dyeing: silicone emulsion defoamer. Jet dyeing is best to choose polyether silicone, high temperature defoaming, low temperature water soluble, non-staining fabric.

Dipetrochemical industry


01 Drilling: ethyl silicone oil (or methyl silicone oil layer emulsion) is used as a slurry additive. 02 Oil production: oil and gas separation, defoaming rod. The melting point is 2.8¬13.9℃ higher than the wellhead foam temperature. 03 Natural gasoline absorption: Use gasoline to mix dimethyl silicone oil into 2% solution. Oil and gas separation demulsification: A. Oil and gas separation, adding 0.025 ~ 0.0065mg/Kg of crude oil can improve production capacity;
B. Demulsification: oil and gas separation of crude oil is generally micro W/O emulsion, adding about 0.2mg/Kg of appropriate defoamer, can achieve the effect of demulsification and defoamer. 05 Refining: vacuum distillation adds defoamer, the color of the fraction is improved, the range of the fraction is relaxed, and the diesel solution with silicone oil is commonly used. 06 High energy fuel (internal combustion, jet fuel, aviation fuel) with cyanide alkyl polysiloxane dispersed in high flash point kerosene, and then added to high energy fuel as a high efficiency defoaming agent. 07 Asphalt and residual oil: Add 0.2×10-6 ~ 2.0×10-608 silicone oil Delayed coking, coke removal, scale elimination: Add defoamer Reference: 0.05 ~ 100×10-609 defoamer drilling fluid: high viscosity sulfonate metal salt (petroleum calcium sulfonate: sodium sulfonated asphalt = 1: 1), the amount of siloxane added is about 100 ~ 400×10-6 or 5 ~ 15mg/Kg, sulfonate: siloxane close to 1:1 is better. 10 Lubricating oil: such as internal combustion engines, automotive lubricants, metal working fluids, compressor oil, etc., when silicone oil is added for defoaming, it is because of the following advantages: A. Insoluble in lubricating oil, in a dispersed state, is conducive to adsorption on the bubble film bubble breaking;
B. There are alkyl groups similar to mineral oil, which can squeeze into the bubble membrane and weaken the molecular attraction;
C. Low surface tension, good penetration, when adsorbed on the surface of the bubble film, the local surface tension is reduced, and the bubble is broken due to uneven surface tension of the bubble film. Heavy oil is selected with small viscosity silicone oil, and the addition amount is 1 ~ 10×10-6. In addition, alkyl polyacrylates are also better and have better gas release. Branched chain amine added to crude gasoline, naphtha, and then added to the lubricating oil, can also be used as a defoamer, adding a small amount of 0.05 ~ 1%, this defoamer can be added to the metal cutting fluid.






Three paper industry

01 Pulping: silicone emulsion defoamer (90g/T paper).


02 Coating paper: coating paint, paper for printing pictures after calender, etc., coated bubbles are generally coated with non-silicon defoamer.


03 Sewage treatment: water-emulsion silicone defoamer.








The application of paint and ink

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1. Requirements for defoamer in coating production:


(1) It has a certain affinity with the active substance on the surface of the foam, but it should be insoluble and insoluble in the bubble liquid; (2) The surface tension is lower than the surface tension of the foaming solution, and has a lower HLB value; (3) The emulsion (latex) should be stable; (4) The coating film can not cause the adverse consequences of fisheye and shrinkage; (5) Water-based coatings with defoamer: the use of insoluble substances in water, such as mineral oil, advanced alcohol, silicone resin, silicone is the best water-based coatings defoamer. Non-water-based coating defoamer: commonly used insoluble in organic solvents, such as low-grade alcohols, silicone resin (silicone resin dosage should be appropriate, excessive easy to shrink and crack, now more modified silicone resin or emulsified silicone resin) picture
2. Silicone defoamer recommended for water-based coatings


(1) Silicone oil, hydrophobic SiO2 mixture is suitable for: epoxy resin, pouring coating, dosage 0.3%; Thermoplastic acrylic resin, spray, dosage 0.3% (2) polyether-polysiloxane and hydrophobic SiO2 mixture: thermosetting alkyd resin, dip coating amount 0.3%, scraping amount 0.1% (3) Hydrophobic SiO2, hydrocarbons, silicone oil mixture: thermoplastic acrylic resin, printing, ink, dosage 0.1%; Air-dried acrylic resin, poured, dosage 0.5%. (4) Silicone oil and hydrophobic SiO2 mixture emulsion is suitable for: alkyd modified styrene acrylic resin, poured and coated, the amount of 0.5%






Silicone defoamer for detergent industry

Polysiloxane and modified sodium tripolyphosphate are used as powder detergent additives, and dimethylsilicone oil (1500c.s) emulsion containing SiO2 of 2 ~ 6% is mixed with anhydrous sodium tripolyphosphate, and the emulsion dosage is 10 ~ 40% to form hydrate as an additive.


Metal cleaning solution, required to be alkali resistant, preferably transparent and antifoaming when added to the liquid product.










Silicone defoamer for food industry


Food special polysiloxane resin: dimethylpolysiloxane as the main body, containing less than 15% SiO2 food is an aqueous solution, with its emulsified products, other can be directly oil-type products, the amount of control.