Aerosil
Description
[Evonik] A registered trademark for an ultra-fine powdered Silica that was first made in 1942 at Degussa. Aerosil® is a colloidal form of silica that is a very light and fluffy powder. It is made by burning silicon tetrachloride in a hydrogen-oxygen furnace. This produces spherical particles; the particle size can be controlled and varying grades are available ranging in size from 4 to 25 micrometers. The fine particle size provides a high surface area. Aerosil® particles can absorb water up to 40% of their own weight and still perform as a powder. It is used as a filler, thickener, and as a matting agent in paints.
Synonyms and Related Terms
aerosol silica; amorphous fumed silica; hydrophilic silica; fumed silica gel
Applications
- Thickener
- Defoamer
- Sorbent
Personal Risks
- Inhalation may cause silicosis; use dust mask.
- Particles can irritate eyes.
- CDH Fine Chemical SDS
Collection Risks
- Non-flammable.
- Inert.
Physical and Chemical Properties
- pH = 3.6-4.5
- CAS = 112945-52-5
- Melting Point = 1700 C
- Density = about 2.2 g/ml
- Refractive Index = 1.45
Resources and Citations
- Evonik: History of Aerosil
- Evonik: Aerosil brochure
- G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 709
- Ceramics and Glass Conservation Section, List of Workshop Materials, The British Museum, London
- MSDS Sheet at MFA: old CAS# = 68611-44-9
- www.walsh-assoc.com/continue.html