Structural Characteristics of Polyether Modified Silicone Oil Defoamer


At present, polyether modified silicone oil PESO is one of the most widely used silicone oils in production. It is synthesized by linking the main or side chains of linear dimethyl silicone oil with polyether chain. It is the most widely used modified silicone oil in the market. The oxygen atoms in the polyether chain of this silicone oil can form hydrogen bonds with water, which can be dissolved in aqueous solution. The polysiloxane chain is neither hydrophilic nor hydrophilic, and the alkyl groups in its main chain are not hydrophilic. Therefore, the polyether and polysiloxane segments are linked together by hydrosilylation to form chemical bonds, forming a unique non-ionic surfactant. Due to the variety of polyethers, a series of different polyether modified silicone oils will be produced by introducing changes in the way of reaction, which have different properties and functions and can meet the needs of diversified markets.


PESO defoamers are mainly polyether modified silicone oils with five types of structure: AB, ABA or BAB, AB, side chain and branched chain. A and B sub-N represent polysiloxane and polyether segments respectively. Among them, the Si-O-C type is the condensation of silicone oil and polyether, which belongs to hydrolysis type. Literature studies [19] show that even hydrolysis, the defoaming performance is still remarkable.


PESO defoamer combines the water solubility of polyether and the low surface tension of organosilicon. It has the hydrophilic group EO and hydrophobic group PO in the polyether chain. If the ratio of them is adjusted properly, it will have a strong low surface tension and strong defoaming ability. It will increase the surface water absorption and carbonization depth of concrete, thus improving the surface performance of concrete as a whole.


Transfer from China Admixture Network