The active ingredient formed by dimethyl silicone oil and fumed silica in the silicone defoamer is added to the foam system, and because the active ingredient has low surface activity, it is quickly distributed to the surface of the liquid to form a new elastic film, that is, to terminate the generation of foam. On the other hand, the active ingredient diffuses to the surface of the elastic film of the foam, further diffuses and penetrates to the surface of the film, which makes the wall of the film thin rapidly and destroys the equilibrium stabilization system of the foam. The foam is strongly pulled by the surrounding liquid with high surface tension, leading to the rupture of the foam. The insoluble system silicone-type defoamer molecules enter the surface of another foam membrane again, and all the foam is repeated.
Silicone defoamer uses problems:
Turbidity problem, sometimes we will find that the use of defoamer after creating a cloudy foaming system, which is due to silicone oil being completely consumed by hydrophobic particles after a phenomenon, the main reason lies in the choice of silicone defoamer components. Avoid the method lies in the selection of high-performance silicone defoamer.
The oil bleaching problem is due to the lack of dispersion of silicone defoamer, when the distribution is not strong, it is easy to appear oil bleaching problem, the solution lies in the dilution of silicone defoamer, dilution medium as far as possible to choose water or a surfactant in the foaming system.
Foam inhibition time problem, the use of silicone defoamer may appear foam elimination, but not foam inhibition, foam again within a short period of time, one is due to the defoamer itself not having strong foam inhibition, and the second is not the right way to use, to avoid the problem of foam inhibition, try to choose high-performance silicone defoamer, followed by the correct use of defoamer.
Features of silicone defoamer:
Silicone defoamer not only has a good defoaming, and foam inhibition effect but also has low consumption, good chemical inertia, and the characteristics of the role in harsh conditions. In recent years, it has developed rapidly, new varieties and models suitable for different use environments continue to arise, and the scope of the application continues to expand. The future will further develop the applicability, and can further improve product quality and equipment utilization of new silicone defoamer, especially the excellent performance of polyether-modified silicone defoamer and emulsion defoamer.