Pure organosilicon, such as dimethyl silicone oil, does not have an antifoaming effect. However, after emulsification, the surface tension decreases rapidly, and the very small amount of it can achieve strong foaming and antifoaming effect, so it becomes an important ingredient of antifoaming agent. Silicone oil type defoaming agent generally has a higher defoaming efficiency, the key to its use is the emulsification of silicone oil. If emulsification is not complete, it will break the emulsion when used, affecting its use effect. Commonly used silicone defoaming agents are silicone oil as a basic component, with appropriate solvent, emulsifier or inorganic filler prepared. Silicone as an excellent defoaming agent, remove the defoaming power is strong, especially valuable is that siloxane set chemical stability, physiological inertia and high and low temperature performance and other characteristics in a body, so it has been widely used.
Because of its lipophilic properties, silicone oil has a satisfactory effect on the defoaming of oil-soluble solutions.
Silicone defoaming agent is a kind of defoaming agent with low toxicity, anti-oxidation and strong foaming ability, but it has poor foaming inhibition ability, large consumption, poor effect on slightly acidic fermentation, and certain inhibitory effect on mycelium development. Therefore, the application in the fermentation industry is limited to a certain extent; In the textile printing and dyeing industry, especially in the use of light-colored fabrics, because of the silicon spots are not easy to clean and again limited.