AEROSIL® fumed silica in plastics

AEROSIL^® fumed silica is a highly dispersed silicon dioxide. Hydrolysis of chlorosilanes in an oxygen-hydrogen flame, produces a fine, amorphous white powder of very high purity. The extremely small primary particles result in a large specific surface area, ranging from 50 to 380 m²/g. Using the AEROSIL^® process, other special oxides such as fumed Aluminium Oxide, Titanium Dioxide or Zirconium Dioxide have been developed. AEROSIL^® fumed silica is invented to improve the manufacturing, quality and performance of thermoplastics, thermosets, polymer composites and elastomers.

Both hydrophilic and hydrophobic types of AEROSIL^® fumed silica are mainly used in polymers, polymer composites and engineering plastics as additive for rheology control, thixotropy, anti-plate-out, anti-blocking, anti-sedimentation, as free flow agent in powder polymers and resins, and for better water resistance. The addition of AEROSIL^® fumed silica to thermoplastic polymers can decrease the MFR (melt flow rate), so that the processing can be improved and dripping (e. g. of cables) will be prevented during heating.

In polymer powders and granules AEROSIL^® fumed silica and AEROXIDE^® Alu C improves the free flow and anti-caking effect, controls the electrostatic charge and works as processing aid in the sintering process.

In elastomers AEROSIL^® fumed silica and AEROXIDE^® TiO₂ P 25 improves the reinforcing effect, hardness, mechanical properties and heat stability.