Silicone rubber has excellent properties such as high temperature, low temperature, weather resistance and ozone resistance. It has been widely used in various fields of the national economy. However, silicone rubber is flammable and will continue to burn, which limits its application in electrical and electronic, wire and cable, automotive, aerospace and other fields to a certain extent. The following small series to introduce the flame retardant silica gel to addMagnesium hydroxideWhat will it do.
After adding magnesium hydroxide to the silicone rubber, the limiting oxygen index increased, and increased with the increase of the amount of magnesium hydroxide. The dispersion of magnesium hydroxide treated by silicone rubber is more uniform, and the aggregated particles are smaller, the magnesium hydroxide particles and silicone rubber are closely combined, and the compatibility with the silicone rubber interface is improved.
       Magnesium hydroxide in the decomposition process will absorb a large amount of heat in the combustion zone, reduce the temperature of the combustion. 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 playing a flame retardant effect.
       In order to expand the scope of use of silicone rubber, flame retardant modification has become one of the main research directions. Early flame retardants for silicone rubber are mainly decabromodiphenyl ether, chlorinated paraffin and other halogen flame retardants and red phosphorus, phosphate and other phosphorus flame retardants. Although these flame retardants have a good flame retardant effect on silicone rubber, they are harmful to the environment due to the release of harmful gases during combustion.
       However, magnesium hydroxide will help to improve its dispersion in silicone rubber and improve its interfacial compatibility with silicone rubber, so that silicone rubber has flame retardancy while maintaining good mechanical properties.
       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, and the damage of silicone treated magnesium hydroxide to the electrical insulation and mechanical properties of silicone rubber is lower than that of the other two kinds of silicone rubber with magnesium hydroxide as flame retardant.
       Above is the role of adding magnesium hydroxide in flame retardant silica gel. Hope can help to everybody.