Silicone rubber has excellent performances such as high and low temperature resistance, weather resistance and ozone resistance, widely used in various fields of the national economy. However, silicone rubber is flammable and will continue to burn in the event of an open flame, which limits its application in electrical and electronic, wire and cable, automotive, aerospace and other fields to a certain extent.
In order to expand the use of silicone rubber, flame retardant modification has become one of the main research directions. Therefore, surface modification of magnesium hydroxide will help to improve its dispersion in silicone rubber and improve its interfacial compatibility with silicone rubber, so that silicone rubber has good flame retardancy while maintaining good Mechanical properties.
After adding magnesium hydroxide to silicone rubber, the limiting oxygen index increases and increases with the amount of magnesium hydroxide. The silicone-treated magnesium hydroxide is uniformly dispersed in the silicone rubber, and the aggregated particles are small, the magnesium hydroxide particles and the silicone rubber are tightly combined, and the compatibility with the silicone rubber interface is improved.
Magnesium hydroxide absorbs 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 the decomposition can dilute the combustible gas, and the water vapor can also isolate the contact between the silicone rubber and the oxygen, thereby functioning as a flame retardant.
All in all, 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. Silicone treated magnesium hydroxide has lower damage to electrical insulation properties and mechanical properties of silicone rubber than the other two. A kind of silicone rubber in which magnesium hydroxide is a flame retardant.