Chemical Industry | Fumed Silica
Typical Applications of Fumed Silica
Fumed silica is an extremely small particle with enormous surface area, high purity, and a tendency to form chains in the chemical manufacturing process.
Fumed silica serves as a universal viscosity builder and an anti-caking agent (free-flow agent) in powders.
Common uses include:
- In cosmetics for its light-diffusing properties
- In products like toothpaste, as a light abrasive
- As a filler in silicone elastomers
- As a viscosity adjustment in paints, coatings, printing inks, adhesives and unsaturated polyester resins
- In the production of cat litter box filler, and
- As a core material in the production of vacuum insulated panels
The Process
Depending on whether a liquid is polar or non-polar, shear will help either decrease or increase viscosity. In many applications, the fumed silica is used as a thickening agent and the degree of homogenization will determine just how well the silica particles bond to one another to form an effective lattice network.
The Sonic Mixing Solution for Dispersing Fumed Silica
The Sonic Sonolator effectively disperses and homogenizes fumed silica liquid slurries into polyester resins, generating the desired thixotropic index and eliminating gel agglomeration, at only 500 psi! Much lower pressures than the 5,000 psi often suggested.
Silica premix is forced through a specially engineered orifice by a PD pump, generating pressure and cavitation. The mix exits the orifice at extremely high velocity, striking a blade in its path that helps generate excessive cavitation. When the fluid slurry is forced through the dispersion chamber, the acceleration and cavitation inside violently rips solid agglomerates apart, forcing smaller particles into a uniform suspension. The combination of fluid acceleration, cavitation and pressure working together, significantly reduces silica agglomerates, thereby improving thix index, product stability and appearance.
Sonic’s unique Sonolator homogenizer has been used extensively for dispersing fumed silica into various components such as resin, glycol, water and more to produce paper and film coatings, defoamers, binders, cosmetic thickening agents, and more.
