definition:

White amorphous powder. Also known as caustic magnesite, light burnt magnesia, etc., the suspension of magnesium hydroxide in water is called magnesium hydroxide emulsion, referred to as magnesium emulsion, and the English name is Magnesium hydroxide. Magnesium hydroxide is a colorless hexagonal crystal or white powder, hardly soluble in water and alcohol, soluble in dilute acid and ammonium salt solution, and the aqueous solution is weakly alkaline. The solubility in water is very small, but the water-soluble part is completely ionized. The concentration of the saturated aqueous solution is 1.9 mg/L (18°C). Heating to 350°C loses water and generates magnesium oxide. The natural mineral brucite of magnesium hydroxide. Can be used for sugar and magnesium oxide. Because magnesium hydroxide is abundant in nature and its chemical properties are similar to aluminum, users have begun to use magnesium hydroxide instead of aluminum chloride for deodorant products. Used as analytical reagent, also used in the pharmaceutical industry

Physical and chemical properties:

Appearance and properties: odorless white powder

Density: 2.36g/cm3

Melting point: 350ºC (Decomposes)

Boiling point: 100ºC at 760mmHg

Flash point: will not burn

Stability: Stable.

Storage conditions: Store in a cool, dry, well-ventilated area away from incompatible substances. Keep containers tightly closed.

Chemical nature

Magnesium hydroxide is a medium-strong base (magnesium hydroxide has very little solubility, and the solution is very weak, sometimes as a weak base treatment). It is dehydrated and decomposed when heated to 350°C: Mg(OH) 2 →MgO+H2O, easily soluble in acid Or ammonium salt solution. Like magnesium oxide, it easily absorbs carbon dioxide in the air, and gradually forms a basic carbonate of 5MgO•4CO2•xH2O. It decomposes into magnesium oxide and water when it is higher than 350℃, but it can be completely dehydrated only when it is above 1800℃.

Application areas:

1. Magnesium hydroxide is an excellent flame retardant for plastic and rubber products. As a flue gas desulfurizer in terms of environmental protection, it can replace caustic soda and lime as a neutralizer for acid-containing wastewater. It is also used as an oil additive to prevent corrosion and desulfurization. In addition, it can also be used in the electronics industry, medicine, sugar refining, as insulation materials and manufacturing other magnesium salt products.

2. Magnesium hydroxide has excellent buffering properties, reactivity, adsorption and thermal decomposition properties. It can be used as chemical materials and intermediates, as well as a green flame retardant and additives for rubber, plastics, and fibers. And resin and other polymer materials industry. Magnesium hydroxide is mainly used as flame retardant, acidic wastewater treatment agent, heavy metal removal agent, flue gas desulfurizer, etc. in the field of environmental protection. [2]

3. This product can be used as a flame retardant or flame retardant filler to be added to polyethylene, polypropylene, polystyrene and ABS resin. It has a good flame retardant and smoke suppression effect. The addition amount is 40-20 parts. However, it is necessary to use anionic surfactants to treat the surface of the particles. Inexpensive anionic surfactants such as higher fatty acid alkali metal salts or alkyl sulfates and sulfonated succinate esters can be used, and the amount is about 3%. This product is also used in the manufacture of magnesium salts, the refining of sugar, the pharmaceutical industry, and daily chemical industries.

4. Magnesium hydroxide is a new type of filled flame retardant. It releases bound water when it is thermally decomposed and absorbs a large amount of latent heat to reduce the surface temperature of the synthetic material it fills in the flame. It can inhibit polymer decomposition and The effect of cooling the generated combustible gas. Magnesium oxide produced by decomposition is a good refractory material and can also help improve the fire resistance of synthetic materials. At the same time, the water vapor it emits can also be used as a smoke suppressant. Magnesium hydroxide is recognized as an excellent flame retardant with three functions of flame retardancy, smoke suppression and filling in the rubber and plastic industry. It is widely used in polymer materials such as rubber, chemicals, building materials, plastics and electronics, unsaturated polyester, paints, and coatings. Especially for mine air duct coated cloth, PVC whole core conveyor belt, flame-retardant aluminum-plastic board, flame-retardant tarpaulin, PVC wire and cable material, mining cable sheath, cable accessories, flame retardant, smoke suppression and antistatic , Can replace aluminum hydroxide, has excellent flame retardant effect. Compared with similar inorganic flame retardants, magnesium hydroxide has better smoke suppression effect. Magnesium hydroxide has no harmful emissions during production, use and disposal, and it can also neutralize acid and corrosive gases generated during combustion. When used alone, the dosage is generally 40% to 60%. It has good compatibility with the base resin and is an excellent flame retardant for thermoplastic resins and rubber products. It is often used as an additive flame retardant or flame retardant filler in adhesives. The reference amount is 40 to 200 parts. Industrially used to manufacture magnesium salts, activated magnesium oxide, medicines, fine ceramics, thermal insulation materials, sugar refining, flue gas desulfurizers, oil anticorrosive additives, acid-containing wastewater neutralizers, color TV picture tube cone glass coatings, etc.

5. The product is also used in the manufacture of magnesium salts, the refining of sugar, the pharmaceutical industry, and daily chemical industries. At the same time, the water vapor it emits can also be used as a smoke suppressant. Magnesium hydroxide is an excellent flame retardant with three functions of flame retardant, smoke suppression and filling in the rubber and plastic industry.

6. The milky suspension of magnesium hydroxide is used as an antacid and a laxative in medicine.