High-temperature vulcanized silicone rubber is a polyorganosiloxane (ie, raw rubber) with high molecular weight (molecular weight is generally 400,000 to 800,000), adding reinforcing fillers and other additives, using organic peroxide as a vulcanizing agent, and press molding (Molding, extrusion, calendering) or injection molding, and cross-chained into rubber at high temperature. This rubber is generally referred to as silicone rubber.

The vulcanization of high-temperature vulcanized silicone rubber is generally divided into two stages. The first stage is to mix the raw silicone rubber, reinforcing agent, additive, vulcanizing agent and structure control agent, and then add the mixed material in the metal mold. Pressure heating molding and vulcanization, the pressure is about 50 kg/cm2, the temperature is 120 ~ 130 ° C, and the time is 10 ~ 30 minutes. Bake at 250°C for several hours to 24 hours. The rubber is further vulcanized, while the organic peroxide is decomposed and volatilized.

The reinforcing filler for silicone rubber is various types of silica, which can increase the strength of the vulcanizate tenfold. Adding various additives is mainly to reduce the cost of the rubber, improve the properties of the rubber, and give the vulcanized rubber various special properties such as flame retardancy and electrical conductivity. The cross-linking agent is various organic peroxides, such as benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, dicumyl peroxide, 2,5-di-tert-butylperoxyhexane, etc. .Structure control agent is added in order to prevent the compounded rubber from being placed for too long, resulting in "structured" and making the rubber compound hard and difficult to process and mature. Methyl hydroxy silicone oil or diphenyl dihydroxy radane can be used. as a structural control agent.

The pendant groups on the main chain of the silicone rubber can be methyl, ethyl, vinyl, phenyl, trifluoropropyl and the like. Methyl groups are most commonly used, but other groups can also be introduced to improve processability and other properties. Therefore, according to the different side groups and compound formulations, various silicone rubbers for different purposes can be obtained, which can be generally divided into the following types: general-purpose (containing methyl and vinyl), high-temperature and low-temperature (containing phenyl, methyl and vinyl), low compression set (with methyl and vinyl), low shrinkage (devolatilization) and solvent resistance (fluorosilicone rubber), etc.