Fireproof coating is one of the varieties of special coatings, is an important part of the fireproof building materials. Fire retardant coatings are generally used on the surface of steel structure substrates, which can reduce the flammability of the steel surface, block the rapid spread of fire, and improve the fire resistance of steel. The excellent performance of fire retardant coating coated on the surface of the substrate, not only can play a decorative role, but also anti-corrosion, rust, acid and alkali resistance, anti-smoke, etc., more importantly, when the fire occurs when the fire retardant coating can prevent the spread of flame, control the development of fire, the internal structure to play an effective protective role.Magnesium hydroxideAs a representative of inorganic flame retardants, with its good thermal stability, non-volatile, non-precipitation, no toxic gases, no pollution and many other advantages, it plays an increasingly important role in fireproof materials.

The flame retardant system material is the core of the fire retardant coating, and its performance has a great influence on the performance of the fire retardant coating. There are inorganic and organic flame retardants. Inorganic flame retardants are mainly additive, including antimony flame retardants, aluminum hydroxide, magnesium hydroxide flame retardants, phosphorus-containing inorganic flame retardants, boron-containing and molybdenum-containing flame retardants and smoke suppressants. They have the characteristics of thermal stability, low toxicity, no corrosive gas generation and lasting flame retardant effect. However, due to their large filling amount in high polymers and the influence of their inherent characteristics, will reduce the polymer processing formability, mechanical properties, electrical properties, etc.

Magnesium hydroxide as the most popular environmentally friendly flame retardant, added to the fire retardant coating has a good flame retardant effect, with fire resistance, high adhesion, good water resistance, no toxic gases and so on. At present, the amount of magnesium hydroxide flame retardant is increasing at a rate of 20% per year, which has a broad market prospect. On the other hand, nanomaterials have the characteristics of small size effect, surface and interface effect, quantum size effect and macroscopic quantum tunneling effect, as well as the advantages of low filling amount and high flame retardant efficiency. According to the above characteristic requirements, the surface of magnesium hydroxide can be modified to nano-magnesium hydroxide, and the flame retardant effect of nano-magnesium hydroxide as a fire retardant coating will be better.