Antimony oxide, commonly known as antimony trioxide, is an inorganic compound with the chemical formula Sb₂O₃. It is also referred to as antimonous oxide or antimony sesquioxide. In its pure form, Sb₂O₃ is a fine, white, odorless powder valued for its versatility and functional properties.
Sb₂O₃ is used primarily as a flameretardant synergist, especially in plastics, rubber, and textile applications, where it enhances the effectiveness of halogenated flameretardant systems. Beyond fireretardant uses, antimony oxide also serves important roles in:
- Electronic components
- Pigments and opacifying agents
- Filling and reinforcing materials
- Catalysts in organic synthesis, including PET production and other polymerization processes
Its combination of chemical stability, optical properties, and catalytic activity makes Sb₂O₃ a widely used industrial additive across plastics, coatings, electronics, and chemical manufacturing.
General Properties
| Properties | Value |
| Chemical formula | Sb2O3 |
| CAS Name | 1309-64-4 |
| EC / EINECS Number | 215-175-0 |
| Molar mass | 291.518 g/mol |
| Appearance | White solid |
| Melting point | 656 °C (1,213 °F; 929 K) |
| Boiling point | 1,425 °C (2,597 °F; 1,698 K) (sublimes) |
| Density | 5.2 g/cm3, α-form 5.67 g/cm3 β-form |
| Solubility in water | 370 ± 37 µg/L between 20.8°C and 22.9°C |
| Solubility | Soluble in acid |
Product Availability
We provide high-purity Antimony Oxide (Sb2O3) tailored for semiconductor and industrial requirements.
| Purity | Up to 99.9999% |
| Forms | Powder |
| Particle Sizes | From -50 mesh to -325 mesh |
| Nanoparticle Sizes | From 10 nm to 100nm |
| Package | Up on request |
If you are in need of any high purity Antimony Oxide (Sb2O3), please contact our sales team for details at sales@american-gmg.com.