Silicone rubber products second vulcanization is also called after vulcanization. The role of secondary vulcanization: When silicone rubber is vulcanized by peroxide, the decomposition of peroxide triggers the reaction of polymer, which generates low molecular compounds (such as benzene and benzoic acid, etc.) in the rubber will affect the mechanical properties of rubber. Moreover, after the first stage of heating and molding of silicone rubber, its cross-link density is not enough, to make it further vulcanization reaction to increase the density of silicone rubber. The pull-up strength, resilience, hardness, swelling, density and thermal stability are all improved compared with primary vulcanization. If the secondary vulcanization is not carried out, the performance of the silicone rubber produced may be affected to a certain extent, and better performance products will not be obtained. The parameters of primary vulcanization may be different from those of secondary vulcanization, which is related to the actual operation! There are various kinds of silicone vulcanization, such as high temperature and room temperature. According to the high temperature silica gel to take an example, before vulcanization is what we usually say raw rubber, mixing rubber is a lot of additives such as vulcanizing agent, release agent and raw rubber together with refining and. From the appearance of a look can be seen. It is not elastic when it is torn by hand. If the rubber is mixed at a certain temperature and vulcanized at a certain temperature, you can get the product, just like the silicone phone cases we usually see, as long as the manufacturer can provide food certification, generally speaking, they are non-toxic.