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NH4B5O8 · 4H2O Ammonium Pentaborate Tetrahydrate
France
Borates are used in lithium-ion batteries and supercapacitors.
Use U.S. Borax products in fire retardants for polymers, cellulose, and wood.
Enhance insulation fiberglass and help protect cellulosic insulation from fire.
Borates help protect ferrous metals from oxidation and harden steel.
Polymers incorporate borate fire-retardant additives to meet safety standards.
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Molecular weight: 272.15
Specific gravity: 1.58
Appearance: White crystalline granules
Solubility: About 10.9% by weight at room temperature
Stability: Ammonium pentaborate shows little tendency to cake except after prolonged storage or if it becomes severely wetted by rain or substantial water penetration. It is also capable of absorbing moisture if exposed to a humid environment.
Boric oxide, B2O3: 63.95%
Ammonium oxide, (NH4)2O: 9.57%
Water of crystallization, H2O: 26.48%
Containers: Products may be available in bulk, IBCs, or small bags
Ammonium pentaborate results from the controlled reaction of ammonia, water, and boric acid. It is an alkaline salt and consists of white crystalline granules.
The product is stable to about 230°F (110°C), at which point it loses all but two moles of water. If heated sufficiently, it releases the balance of its hydration water and decomposes to boric oxide and ammonia.
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