Application of Magnesium Hydroxide

Silicone rubber has excellent properties such as high temperature, low temperature, weather resistance, ozone resistance, etc. It has been widely used in various fields of the national economy. However, silicone rubber is flammable and will continue to burn, which to some extent limits its application in the fields of electronics, wires and cables, automobiles, aerospace, etc. The following is a brief introduction to the application of magnesium hydroxide in flame retardant silica gel. After adding magnesium hydroxide to silicone rubber, the limiting oxygen index increases, and increases with the increase of magnesium hydroxide dosage. The dispersion of magnesium hydroxide treated by organic silicon in silicone rubber is relatively uniform, and the aggregated particles are small. Magnesium hydroxide particles are closely combined with silicone rubber, and the compatibility with silicone rubber interface is improved. Magnesium hydroxide will absorb a large amount of heat in the combustion zone during the decomposition process, reducing the temperature of the combustion products. At the same time, the water vapor generated by decomposition can dilute combustible gas, and the water vapor can also isolate the contact between silicone rubber and oxygen, thus playing a flame retardant role. In order to expand the application range of silicone rubber, flame retardant modification has become one of the main research directions. Early flame retardants used in silicone rubber mainly include halogenated flame retardants such as decabromodiphenyl ether and chlorinated paraffin, and phosphorus flame retardants such as red phosphorus and phosphate ester. Although these flame retardants have good flame retardant effect on silicone rubber, they will release harmful gases when burning, thus causing great harm to the environment. At the same time, magnesium hydroxide does not release harmful gases during combustion, and the residue after combustion will not pollute the environment, so magnesium hydroxide is increasingly widely used as an environment-friendly flame retardant. However, magnesium hydroxide has obvious flame retardant effect only when it is added in a large amount, and a large amount of magnesium hydroxide will cause great damage to the mechanical properties and electrical properties of silicone rubber. Therefore, surface modification of magnesium hydroxide will help to improve its dispersion degree in silicone rubber and its interfacial compatibility with silicone rubber, thus making silicone rubber maintain good mechanical properties while having flame retardancy. In a word, magnesium hydroxide has a good flame retardant effect on silicone rubber. The flame retardant effect of silicone-treated magnesium hydroxide is better than that of stearic acid-treated magnesium hydroxide and untreated magnesium hydroxide. The damage of silicone-treated magnesium hydroxide to the electrical insulation and mechanical properties of silicone rubber is lower than that of other two kinds of silicone rubber with magnesium hydroxide as flame retardant. The above is about the application of magnesium hydroxide in flame retardant silica gel, hoping to help everyone.