Chemical name: barium metaborate
CAS accession number: 13701-59-2
Product specifications:
Appearance : white orthorhombic crystalline powder
Chemical formula ：Ba(BO2)2
Molecular weight：222.95
Melting point ℃ ：1060
Barium oxide % ：60.25
Boron trioxide %： 22.96
Silica % ：6.82
Water soluble fraction % ：0.23
Aqueous suspension PH ：10.14
Sieve residue % ：0.17
Oil absorption %： 25.24
Volatile %： 0.92
Crystal water % ：9.74
◆Nature:known barium metaborate has four hydrates: monohydrate, dihydrate, tetrahydrate, and pentahydrate, which are slightly soluble in water and easily soluble in hydrochloric acid.
◆Application:primer and topcoat used in the coating industry. It is a new type of anti-rust pigment and is also used in ceramics, papermaking, rubber and plastics industries. Used as an additive flame retardant, the flame retardant efficiency is not as good as antimony oxide, but because of its low price, it can be used as a substitute for antimony oxide flame retardants, and it has a synergistic effect with halogen-containing flame retardants. Suitable for epoxy resin, unsaturated polyester, phenolic resin, polyvinyl acetate, acrylic resin, polyurethane, polyvinyl chloride, etc.
◆Storage method:should be stored in a cool, ventilated and dry warehouse. It is strictly prohibited to pile up with oil substances.
Introduction to barium metaborate
Barium metaborate is a white powder crystal, or triclinic axial scale-like shiny crystal, with a smooth feel and no odor, it can be dissolved in water, alcohol, and glycerin, and an aqueous solution of boric acid into a weak acid. Boric acid has no odor and tastes slightly bitter. It is widely used in glass (optical glass, acid-resistant glass, heat-resistant glass, glass fiber for insulating materials) industry, which can improve the heat resistance and transparency of glass products, improve mechanical strength, and shorten the melting time.
1. Physical and chemical properties
Barium metaborate is a white powder-like solid, odorless and tasteless, with a melting point of 965 ° C, a density of 3.965g/cm3 and a relative molecular mass of 343.4. It is a water-insoluble compound with a solubility of 9.3mg/L in water and a pH of 8.5. Under acidic conditions, barium metaborate is decomposed into boric acid and barium salts.
2. Preparation method
There are many methods for the preparation of barium metaborate, including heating method and precipitation method. The heating method usually uses barium carbonate and boric acid as raw materials, and reacts to produce barium metaborate under high temperature conditions. The precipitation rule is to mix barium nitrate and boric acid into ammonia to obtain barium metaborate precipitation. Different preparation methods will affect the purity and particle size of barium metaborate.
3. Application field
(1) Used in the paint industry primer, top paint, is a new type of anti-rust pigment;
Barium metaborate is slightly soluble in water and releases Ba+ and B2O4- ions, which reverse the electrochemically corroded anode, thereby preventing the hydroxyl group from reacting with ferrous ions to form iron hydroxide (rust). In addition, barium ions can produce barium soap to increase the density of the paint film and reduce the water permeability of the paint film, so barium metaborate has excellent anti-rust properties.
Barium metaborate has good color and low color strength, can be used as the pigment of primer and top paint, and has better anti-rust effect in water-based latex paint.
(2) Used in ceramics, paper, rubber and plastics industries;
Barium metaborate has the advantages of anti-rust, anti-mildew, anti-pulverization, flame retardant, long-lasting color and so on. Particularly valuable is that barium metaborate is non-toxic, in the manufacturing, construction and gas welding cutting painted steel, will not produce toxic phenomenon. It can also be used in houses, vehicles, Bridges, steel structure protective paint and fire retardant paint.
(3) Used as additive flame retardant.
The flame retardancy of barium metaborate is not as good as antimony oxide, but because of its low price, it can be used as a partial substitute for antimony oxide flame retardants, and has synergistic effect with halogenated flame retardants. Suitable for epoxy resin, unsaturated polyester, phenolic resin, polyvinyl acetate, acrylic resin, polyurethane, polyvinyl chloride and so on.
4. Safety precautions
Barium metaborate is a certain dangerous compound, need to pay attention to the following safety matters:
(1) Wear protective gloves and masks when contacting barium metaborate to avoid direct contact and inhalation of dust.
(2) Barium metaborate has a certain corrosiveness and should not be mixed with strong acids and alkali to avoid dangerous reactions.
(3) Barium metaborate should not be stored and exposed to the air for a long time to avoid absorbing moisture and deterioration.
The price of barium metaborate is about 6100-7000 yuan/ton, according to the quotation of the month, the price fluctuates, please consult the customer service of Shanghai art letter station for details.
