IOTA Silicone Defoamer


The most commonly used defoamer is polydimethylsiloxane, also known as dimethylsilicone oil. It has low surface energy, low surface tension, low solubility and high activity in water and oil. Its main chain is silicon-oxygen bond, which is a non-polar molecule. It is incompatible with polar solvent water and has little affinity with general oil. It has low volatility, chemical inertia, relatively stable and less toxicity. Pure polydimethylsiloxane is difficult to be used as defoamer without dispersion treatment. It may be due to its high interfacial tension with water, low spreading coefficient and difficulty in dispersing in foaming media. Therefore, silicone oil is mixed into SiO 2 aerosol, and the composite is made by mixing hydrophobic treated SiO 2 aerosol into dimethyl silicone oil, which is treated at a certain temperature and a certain time.


Silicone defoamer is made by mechanical emulsification of silicone grease, emulsifier, waterproofing agent and thickener with appropriate amount of water. Its characteristics are low surface tension, high surface activity, strong defoaming power, less consumption and low cost. It is not miscible with water and most organic substances, and can defoam most of the bubble media. It has good thermal stability and can be used in a wide temperature range of 5-150 degrees Celsius. It has good chemical stability and is difficult to react with other substances. It can be used in acid, alkali and salt solutions as long as it is properly collocated, without loss of product quality. It also has physiological inertia LD250g/kg mice, which is usually used in food and pharmaceutical industries. It has anti-foaming and defoaming functions for all bubble systems and belongs to the category of broad-spectrum defoamers. It is widely used in defoaming of detergent, paper making, pulp, sugar making, electroplating, fertilizer, additives, wastewater treatment and other production processes. In the petroleum industry, it is widely used for desulfurization of natural gas to accelerate oil-gas separation. It is also used to control or suppress bubbles in drying of ethylene glycol, extraction of aromatic hydrocarbons, asphalt processing, dewaxing of lubricating oil and other devices. In textile industry, it is used for defoaming in dyeing, refining, sizing and other processes; in chemical industry, it is used for defoaming in synthetic resin, latex, paint, ink and other processes; in food industry, it is used for defoaming in various concentration, fermentation and distillation processes. Silicone grease can be coated on the wall of the pot, at the outlet or on the metal mesh for defoaming. Silicone grease can be used as a solution for defoaming in oil phase system. Silicone grease and low viscosity silicone oil can be used as water emulsion, which can be used for defoaming in various aqueous systems. In medicine, it is usually used to remove the flatulence of organs or stomach organs before operation, X-ray and gastroscopy.


There are two kinds of defoamers: one can eliminate the bubbles, such as ethanol, and the other can inhibit the formation of bubbles, such as emulsified silicone oil. The licensed Defoamers in China are emulsified silicone oil, high-carbon alcohol fatty acid ester complex, polyoxyethylene polyoxypropylene pentaerythritol ether, polyoxyethylene polyoxypropylene amine ether, polyoxypropylene glycerol ether and polyoxypropylene.