Barium metaborate monohydrate (BaB2O4•H2O)-Powder

Characteristic

Barium borate is an inorganic compound, a borate of barium with a chemical formula BaB₂O₄ or Ba(BO₂)₂. It is available as a hydrate or dehydrated form, as white powder or colorless crystals. The crystals exist in the high-temperature α phase and low-temperature β phase, abbreviated as BBO; both phases are birefringent.

Formula: BaB₂O₄•H₂O

Formula weight: 240.97 (222.96anhy)

Appearance:white powder or colorless crystals

Melting Point: >900°

Density 3.25-3.35g/ml

Refractive Index: 1.55-1.60

Sensitivity: Ambient temperatures.

Solubility: Solubility in water ≈0.3%. Moderately soluble in dilute acids. Insoluble in organic solvents

Application

BBO is a popular nonlinear optical crystal. Quantum linked photons are producible with beta barium borate. Barium borate is a bactericide and fungicide. It is added to paints, coatings, adhesives, plastics, and paper products.

Barium borate is resistant to ultraviolet radiation. It can act as UV stabilizer for polyvinyl chloride.

The solubility of barium borate is a disadvantage when used as a pigment. Silica-coated powders are available. The alkaline properties and the anodic passivation properties of the borate ion enhance the anticorrosion performance. Commonly available barium metaborate pigment comes in three grades; Grade I is a barium metaborate itself, grade II is compounded with 27% zinc oxide, and grade III is compounded with 18% of zinc oxide and 29% calcium sulfate. Barium borate shows synergistic performance with zinc borate.

Barium borate is used as a flux in some barium titanate and lead zirconate EIA Class 2 dielectric ceramic formulations for ceramic capacitors, in amount of about 2%. The barium-boron ratio is critical for flux performance; BaB2O2 content adversely affects the performance of the flux.

Barium borate-fly ash glass can be used as radiation shielding. Such glasses are superior in performance to concrete and to other barium borate glasses.