Hebei Messi Biology Co., Ltd. stated that magnesium-aluminum hydrotalcite is a new type of multi-effect plastic additive with similar structure and composition to magnesium hydroxide and aluminum hydroxide. It can absorb heat when thermally decomposed, which can reduce the temperature of the combustion system; dilute combustible gases, isolate oxygen at the same time, and play a flame retardant effect. It is a new type of high-efficiency, non-toxic, low-smoke halogen-free flame retardant with great development prospects, so it has great development potential. The main elements are magnesium and aluminum. Magnesium hydroxide is the basic raw material for synthesizing hydrotalcite, and a large amount of magnesium required in the synthesis of hydrotalcite is provided by magnesium hydroxide. The main synthesis methods include coprecipitation method, hydrothermal method, roasting and recovery method, template synthesis method, nucleation/crystallization isolation method, etc.
As a flame retardant, hydrotalcite has the advantages of aluminum hydroxide and magnesium hydroxide flame retardants, and overcomes their respective shortcomings. At present, the main flame retardant materials used in the electrical industry are granular magnesium hydroxide and aluminum hydroxide. In terms of increasing the material temperature, reducing the heat released from the material surface, increasing the natural temperature of the material, and prolonging the ignition time, the effect of aluminum hydroxide is better than that of magnesium hydroxide, while in terms of increasing the spontaneous combustion temperature of the material, increasing the oxygen index, and promoting the carbonization effect, magnesium hydroxide is better than aluminum hydroxide.
Experiments show that when hydrotalcite added to the polymer is thermally decomposed, the inert gas carbon dioxide and water vapor released can dilute the concentration of combustible gas and weaken the fire, and the decomposed magnesium oxide and aluminum oxide can form a heat insulation layer. At the same time, when thermally decomposed, it absorbs heat and reduces the surface temperature of the polymer. It can be seen that hydrotalcite does have three functions: flame retardant, smoke suppressant, and filling. It is a new type of inorganic flame retardant. At the same time, adding high-purity smoke suppressant effectively reduces the amount of smoke generated when the material burns.