Polyether modified organosilicon is a polyether - siloxane copolymer (abbreviated as silica ether copolymer) produced by introducing polyether chain segments into siloxane molecules. It is a kind of defoaming agent which is composed of polyether which has strong anti-foaming ability and dimethyl silicone oil which has strong hydrophobicity and quick anti-foaming ability. It has the characteristics of low surface tension, rapid defoaming, long time of defoaming, low cost, low dosage and wide application. The modification of organosilicon with polyether has made it have the advantage of secondary defoaming agent and become a kind of defoaming agent with excellent performance and broad application prospect.In the copolymer of silica ether, the siloxane segment is the oil-loving group and the polyether segment is the water-loving group. In the polyether segment, the polyoxyethane chain can save energy and provide hydrophilicity and blistering, while the polyoxyethylene chain can save energy and provide hydrophobicity and permeability, which have a strong effect on reducing surface tension. The group at the end of the polyether chain also has a great influence on the properties of the silica ether copolymer. Common end groups are carboxyl, alkoxy, etc. By adjusting the relative molecular weight of siloxane segment in copolymer, the physical property of organosilicon can be highlighted or weakened. Similarly, changing the relative molecular mass of polyether segment will increase or decrease the proportion of organosilicon in the molecule, which will also affect the performance of the copolymer. Organosilicon as spray defoaming agent has been reported in many literatures. In the old dyeing process, dimethyl polysiloxane defoaming agent is generally applied to achieve satisfactory defoaming agent effect and ensure uniform dyeing. The new dyeing process, however, USES high temperature and high pressure machinery, in which the dye is squirted and dyed. Although the foam produced can be defoamed by the ordinary silicone defoaming agent, but at high temperature and pressure, the general siloxane defoaming agent will produce film-like precipitation and dye spots. Block copolymers overcome these disadvantages because they dissolve in cold water and not in hot water. However, the defoaming effect of this copolymer defoaming agent alone is not satisfactory. If a certain amount of fog-like SiO2 is added to the copolymer, the satisfactory defoaming effect can be achieved and uniform dyed fabric can be produced. Polyether modified silicone defoaming agent is easily emulsified in water, also known as "self-emulsifying defoaming agent". Above the temperature of the turbid point, it loses its solubility and mechanical stability to water, and is resistant to acid, alkali and inorganic salt. In addition, it can also be used for the defoaming of diethanolamine desulphurization system and the defoaming of various oil agents, cutting fluid, non-freezing fluid, water-based ink and other systems. It is also suitable for the defoaming of uncured resin after plate making of photosensitive resin in the printing industry. It is a representative, excellent performance and widely used silicone defoaming agent. In order to improve the application of lipophilic in water-based inks, coatings and cutting fluids, some methyl groups are replaced by long-chain alkyl groups in the copolymer molecules of polyether modified organosilicone, which can play a more effective role in defoaming. In order to achieve better defoaming performance at the temperature below the cloud point, commercial self-emulsifying defoaming agents are usually equipped with dimethyl silicone oil -- silica black paste. At this point, polyether modified organosilicone surfactant can be used as the emulsifier of dimethyl silicone oil to play a role of dispersion and emulsification.