Hebei Messi Biology Co., Ltd. stated that magnesium oxide is used as a reinforcing agent for heat-resistant rubber in nitrile rubber. For example, nitrile rubber with 100 parts of magnesium oxide can withstand heat of 177°C. Adding an appropriate amount of magnesium oxide to chloroprene rubber can improve the tensile strength, tensile stress and hardness of its vulcanized rubber, and can neutralize the small amount of hydrogen chloride produced during its vulcanization or when the product is exposed to sunlight, but the heat resistance is slightly poor. Magnesium oxide should be packaged and sealed in polyethylene bags and covered with protective bags. It is necessary to pay attention to moisture-proof, and the storage period should be less than 6-12 months.
The molecular formula of magnesium oxide is MgO. Magnesium oxide is divided into light and heavy. The bulk density of light magnesium oxide is less than or equal to 0.25g/mL, and the heavy one is about three times that of light. Light is a white amorphous powder, odorless and non-toxic; heavy is white or beige powder. Relative density is 3.58, almost insoluble in water and ethanol, soluble in dilute acid and ammonium salt solution. The melting point is 2800°C, with high fire resistance and thermal insulation. If placed in humid air for a long time, it will absorb moisture and carbon dioxide, generate acid magnesium carbonate and deteriorate. Light products are more likely to absorb moisture and carbon dioxide than heavy products. After the magnesium carbonate or magnesium hydroxide is rinsed with water and precipitated, it is dried, crushed, placed in a reverberatory furnace, heated to 800°C-900°C, calcined for 5-6h, cooled, and sieved to obtain the finished light magnesium oxide. If the calcination temperature is above 900°C, the resulting product is heavy magnesium oxide.
Light magnesium oxide is used as a filler and reinforcing agent for rubber and plastics. It can also be used as a vulcanization activator and inorganic accelerator in the rubber industry. It is used as an acid inhibitor in the pharmaceutical industry, as a raw material for catalysts and other magnesium compounds in the chemical industry, and as a raw material for oils, dyes, ceramics, enamel, glass and other industries. Heavy magnesium oxide is mainly used to manufacture refractory materials and thermal insulation materials.