The fumed silica has a small particle size, a large specific surface area, and a silanol group on the surface. These silanol groups can interact with adjacent fumed silica particles to form hydrogen bonds.
Hydrogen bonding causes it to form a thixotropic structure. This network structure makes the particles in the system less prone to coalescence and phase separation. At the same time, the viscosity of the system is also improved to prevent the movement of the components in the system.
As an ideal anti-settling agent, fumed silica is very effective in preventing the precipitation of pigments in coating systems. Especially for the color paste system, the proper addition amount will greatly improve the stability of the color paste to improve the applicability of the color paste and reduce the influence of the color paste on the coating system.
In addition, the anti-settling effect of fumed silica is very advantageous for coating storage. In particular, certain pigments, such as metal powders and flakes, are highly precipitated and cannot be completely suspended. The use of fumed silica ensures that the dispersion does not precipitate.