- CUROX® A-390 is a nearly colorless liquid composed of a peroxide system based on acetylacetone and tert-butyl peroxybenzoate, deactivated with diacetone alcohol.
- It is a free-radical initiator for curing unsaturated polyester resins, primarily used to cure fiber-wound parts in conjunction with cobalt accelerators under both room-temperature and high-temperature conditions.
- Appearance: Virtually colorless liquid
- Active oxygen content: approx. 4.5% (mass fraction)
- Deactivator: diacetone alcohol
- Density (20°C): approx. 1.07 g/cm³
- Viscosity (20°C): approx. 34 mPa·s
- Solubility: Miscible with alcohols and phthalates
- Critical temperature (SADT): Above 60°C
- Recommended storage temperature: 0°C to 25°C
- Shelf life at 25°C: 8 months from the date of manufacture
- Primarily used for curing unsaturated polyester resins, in combination with cobalt accelerators at room temperature.
- Standard dosage: 1–3% of the supply, combined with 0.5–2% of a 1% cobalt solution.
- Not suitable for vinyl resins.
- It exhibits intense heat release, resulting in short demolding times and excellent demolding properties.
- Cures relatively quickly even at low ambient temperatures.
- CUROX® A-390 is standardly packaged in 25-kilogram polyethylene bottles.