Fluorine Silicone Product Environmental Persistence

A fluorosilicone defoamer, wherein the fluorosilicone defoamer has fluorocarbon groups of different segments. Fluorine Silicone Product The antifoaming agent provided by the invention has low surface energy, excellent defoaming performance, long foaming time and low addition amount, Fluorine Silicone Product and is particularly suitable for defoaming in an oily system. The present invention also provides a process for the preparation of a fluorosilicone defoamer comprising reacting a compound represented by the formula (II), trifluoropropylmethylcyclotrisiloxane (D3F) and octamethylcyclotetrasiloxane ( D4), hexamethyldisiloxane is used as a blocking agent, a mineral acid or an organic acid as a catalyst, and the mixture is heated to react to obtain a fluorosilicone defoamer. Fluorine Silicone Product In the preparation, the proportion of each component was optimized, the optimum formulation was obtained, and the obtained fluorosilicone defoamer was excellent in defoaming and foaming performance. At the same time, the invention provides the method of operation simple, mild conditions, suitable for large-scale industrial production.

The fluorine compound used is mainly a compound having 8 or more carbon atoms in the fluoroalkyl chain. It has recently been feared that fluorine compounds having at least 8 carbon atoms in the perfluoroalkyl chain are persistent in the environment due to their difficulty in degradation and higher accumulation. Thus, Fluorine Silicone Product attempts have been made to find a fluorine compound containing a short fluoroether group chain having a lower environmental persistence.

In addition, fluorosilicone compounds having both a silicone moiety and a fluorine moiety in the molecule are also known. Patent Document 3 describes a fluorosilicone compound which is a component of a composition for forming a curable silicone film having water and oil repellency, Fluorine Silicone Product although Patent Document 3 does not describe a compound of the fluorosilicone compound alone Use or mold release.

It has excellent oil resistance and solvent resistance. For aliphatic, Fluorine Silicone Product aromatic and chlorinated hydrocarbon solvents, petroleum fuel, lubricating oil, hydraulic oil and certain synthetic oils (such as diester lubricants, silicic acid Ester hydraulic oil, etc.) at room temperature and high temperature stability are good, and can maintain flexibility. In the oil immersion conditions, Fluorine Silicone Product the maximum temperature of up to 180 ℃. In the normal temperature and high temperature stability are good, can be used in the range of long-term, 250 ℃ short-term use