Apr 11, 2017
Silicone oil surfactant
Dimethicone is low foaming, methylphenylsilicone oil showed a different degree of foaming.
Causing the silicone oil in an organicsolvent solution surface tension reduction, which can make it capable ofdissolving them in the liquid phase enriched surface, having a siliconesurfactant show. Silicone oil can be emulsified in water, resulting in thedecrease in surface tension of water.
This is the reason to do silicone defoamer.Their mode of action with concentration dependent; If in an aqueous system, theconcentration of silicone oil increased, the defoaming more significant role.
According to the theory, being defoamersdefoaming medium must be as insoluble. Because the quality was less totalvolume of liquid absorbed, easier to achieve a high surface concentration, inaddition, pressure distribution must be positive, so that the surface of a thinlayer of foam can rapidly form a closed film. Suds suppressors mask table andthe foaming agent must not form a mixture. In aqueous systems, dimethicone canmeet all these requirements, a minimum because they can be spread in the watersolubility of the volume, and has the characteristics of a number of organicand inorganic most low miscibility.
Silicone lubrication
Dimethicone small force between themolecules, so the low-load performance of its film. In the boundary frictionregion, simethicone combination of steel and steel no lubrication; But forlight load rolling bearings is very good. Such as polyamide, polystyrene orphenolic resin, plastic bearings, lubrication is the best. Within the range ofmetallic materials, and for just a combination of bronze, chromium, zinc orcadmium, or a combination of chrome and bronze also get good results.
Phenyl introduce lubricity can be improved.Methylphenyl silicone oil suitable for the pressure is not too high bearinglubricant. To further improve the lubricity can be obtained by a phenyl groupor a halogenated aliphatic achieved.
Dimethicone lubrication can be improved byvarious additives, e.g., methyl ricinoleate can add greatly improved lubricity.