It belongs to comb like organopolysiloxane. N + m is about 50-250, and the molecular weight is controlled between 1000-150000. The compatibility is adjusted by polyether and polyester. The longer the chain, the better the compatibility. Polyether is the most modified one, usually ethylene oxide and propylene oxide. With the increase of ethoxyl content, its compatibility with water is also improved. Therefore, water-soluble siloxane leveling agent can be synthesized. Ethylene oxide and propylene oxide can be used alone or mixed to control hydrophilicity and lipophilicity. If it contains ethoxy and propoxy at the same time, it can be used as a leveling agent for water and oil siloxanes, such as moneng-1080 and 1090 series products. The larger the molecular weight is, the stronger the surface state control ability is, and the better the skid resistance and adhesion resistance are. For example, moneng-1070 and 1071 series products. There are two ways to join the modified polyester or polyether with siloxane: one is the silicon oxygen bond; the other is the silicon carbon chain. Generally speaking, the thermal stability and water resistance of the former are not as good as those of the latter. The compatibility of polysiloxane modified by polyether and polyester with resin has been greatly improved, the surface tension has been reduced, the ability to control the surface flow, the skid resistance, the anti shrinkage cavity and the anti adhesion effect are also very good, and the interlayer adhesion of some products is also a problem. In particular, polyether modified polysiloxane has poor thermal stability and is easy to foam. Pay attention to the negative effects of these products when applying.