In a broad sense, rubber products are vulcanized to a certain extent. Even if they are not heated, they can continue to deepen the vulcanization process under the action of waste heat, or during the storage of products, or produce continuous crosslinking under dynamic action. Of course, it also includes the processing process of continuous heating for secondary vulcanization; The purpose of secondary vulcanization is to further crosslink rubber products and improve the mechanical properties and compression set properties of rubber products; The method of secondary vulcanization is hot air vulcanization in oven or hot air secondary vulcanization in vulcanization tank; At present, many rubber seals or rubber product production units use secondary vulcanization technology to make rubber seal products. The technology is constantly updated and optimized with the changes of the times!

Function of secondary vulcanization of silicone rubber: when silicone rubber is vulcanized with peroxide, after peroxide decomposition causes polymer reaction, Low molecular weight compounds were formed (such as benzene and benzoic acid) existing in rubber will affect the mechanical properties of rubber. Moreover, after the silicone rubber is heated and formed in the first stage, its crosslinking density is not enough. It is necessary to make further vulcanization reaction to increase the density of silicone rubber. The pull-up strength, resilience, hardness, swelling range, density and thermal stability are greatly improved compared with primary vulcanization. If secondary vulcanization is not carried out, it may be produced The performance of silicone rubber is affected to a certain extent, and no better product can be obtained The parameters of primary vulcanization and secondary vulcanization may be different, which is related to the actual operation! There are many kinds of silicone rubber vulcanization, including high temperature and room temperature. Take high-temperature silicone rubber as an example. Before vulcanization, it is what we usually call raw rubber. Compound is to refine many additives such as vulcanizing agent and release agent together with raw rubber. It can be seen from the appearance. It breaks when pulled by hand. It has no elasticity. If the mixed rubber is vulcanized at a certain temperature, the products can be obtained, as we usually see: silicone rubber bottle cover, silicone rubber bracelet, silicone rubber bottle cover, silicone rubber sealing ring, silicone rubber tray, silicone rubber pad, silicone rubber mobile phone cover, etc