Why is silica needed? What is it used for?

Evonik’s silica products offer advantages to consumers in a wide range of applications. AEROSIL® fumed silicas, for example, are excellently suited for making coatings drip-free and preventing sedimentation of dispersed pigments. Highly porous SIPERNAT® grades are used, for example, to absorb liquid vitamins and other nutrients and thus allow homogeneous distribution of valuable additives in animal feeds; this ensures that the animals are accurately and consistently supplied with the necessary nutrients. ULTRASIL® grades are optimized for good distribution in rubber compounds for car tires, making the tires both fuel-efficient and safe. SIPERNAT® and ZEOFREE® are used to keep powders free flowing and prevent clumping. This is important in the food industry, for example, to ensure consistent quality of food products in powder form. As cleaning particles in toothpastes, ZEODENT® silicas ensure that teeth are cleaned thoroughly but gently. These are just a few examples of the very many areas in which consumers benefit from our silica products. More information is available on our web page:

AEROSIL® fumed silicas allow the rheology of liquids to be adjusted so that dispersed solids do not sediment and coatings, for example, do not run down on a wall. The liquid can still be easily agitated and processed, however, because its viscosity is reduced by shearing. This property is exploited in, for example, paints and coatings, silicone sealing compounds, and adhesives in the production of rotor blades for wind turbines.
Evonik SIPERNAT® and AEROPERL® silicas absorb liquids like a sponge and convert them into free-flowing powders. Even liquids that are sticky or otherwise difficult to process are thus brought into a form that is easy to handle. The absorbates thus obtained are often referred to as “dry liquids”. Examples are rubber additives and vitamins in animal nutrition.
In tread mixes for car tires, synthetic carbon black is now partly being replaced by the silica (ULTRASIL®)- silane system in combination with a special polymer mix. This allows significant improvement in rolling resistance and wet grip. Compared with treads filled with carbon black, this can save fuel and improve driving safety without increasing wear.
Evonik’s SIPERNAT® and AEROSIL® grades of silica ensure that powders flow freely and are easily processed. This is also known as the free-flow effect. Examples are fire extinguishing powders, spice powders, and salt.
ZEODENT® silicas are important constituents of toothpastes. They have a mildly abrasive action and ensure thorough cleaning of the teeth. By special design of the silica, it has been possible to combine high cleaning action (PCR or Pellicle Cleaning Ratio) with low abrasive effect on the teeth (RDA or Relative Dentin Abrasion).