In order to improve the dispersing performance and flame-retardant effect, the magnesium hydroxide is better used for the flame-retardation of the composite of plastic and the like. The magnesium hydroxide as the flame retardant has special requirements, such as small surface area, Molecular material compatibility, easy dispersion and other characteristics. Corresponding to the production of magnesium hydroxide flame retardant, magnesium hydroxide with the need to adopt a different preparation techniques. Usually the room temperature synthesis, according to the different base used. There are three methods: sodium hydroxide, ammonia and calcium hydroxide method.

 

　　General magnesium hydroxide as a flame retardant has its own unavoidable disadvantages: poor compatibility with the polymer, easily lead to lower processing properties of polymers, matrix material properties and mechanical properties are reduced, it can not be used as Use of flame retardants.

 

　　Sodium hydroxide method is based on brine or magnesium chloride as raw material, and sodium hydroxide reaction of magnesium hydroxide; to brine or magnesium chloride as raw materials to brine as a precipitator in the reactor for the reaction method known as the ammonia precipitation method ; Calcium hydroxide precipitation method is to brine or magnesium chloride and other soluble magnesium salt as raw materials, so that reaction with lime milk reaction of Mg (OH)! Precipitation method. Sodium hydroxide and ammonia. The method has the advantages of high industrial application value, but it is only suitable for industries with low purity requirement use. Preparation of magnesium hydroxide, the need for magnesium hydroxide hydrothermal treatment and surface modification and other post-processing.