For compounded silicone rubbers requiring high extrusion flow properties or high dielectric properties, surface modified silica should be used as a reinforcing filler. Cyclic or linear organosiloxane oligomers, alkyl alkoxysilanes, organosilazanes, and straight-chain alcohols can be used for the surface modification of silica. Commonly used, and the treatment effect is better. For example, the application of hexamethyldisilazane to treating silica can make part of the silanol groups on the surface of silica particles replaced with trimethylsilyl groups to become hydrophobic silica, thereby improving the affinity between silica and silicone rubber. The speed of eating powder is increased when mixing the silicone rubber, which can effectively inhibit the structuring effect of the mixed silicone rubber, and improve the mechanical properties and dielectric properties of the vulcanized silicone rubber.