Abstract
Foaming profile differs from one application to others due to the many variables relating to the foaming phenomena such as chemicals in the system, physical and mechnical conditions. Therefore, discussing defoaming or antifoaming exhibits much more complexity than the simple act of foaming. Due to the sheer complexity concerned, the actual technology seems to precede scientific understanding.
In a wide range of industries, silicone antifoams are the most effective antifoams in both aqueous surfactant systems and nonaqueous systems. The efficiency can be explained by the surface chemical characteristics of the silicone polymer, which are derived from its unique structure such as backbone flexibility and low intermolecular forces, especially for polydimethylsiloxane.
In this paper, defoaming by polysiloxane polymers is explained by the surface chemical nature of the polymer. As well, in aqueous systems, enhanced defoaming by compounding hydrophobic silica is explained by dewetting mechanisms based on previous theories.
