Secondary vulcanization, the English name is (postcure), is to bake the product in the oven for a period of time (180 degrees to 200 degrees, usually two hours or three hours) after the product is formed from the machine. ), called the second vulcanization. Secondary vulcanization is also called post-vulcanization. Commonly used for vulcanization of silicone rubber, fluorine rubber and fluorosilicone rubber.

The role of secondary vulcanization: When silicone rubber is vulcanized with peroxide, after the peroxide decomposes and triggers a polymer reaction, low molecular compounds (such as benzene and benzoic acid, etc.) are generated and are present in the rubber, which will affect the mechanical properties of the rubber. Moreover, after the silicone rubber is heated and molded in the first stage, its cross-linking density is not enough. It requires further vulcanization reaction to increase the density of the silicone rubber. The tensile strength, resilience, hardness, swelling degree, density, and thermal stability are all better than those of the first stage. Vulcanization has been greatly improved. If secondary vulcanization is not performed, the performance of the silicone produced may be affected to a certain extent, and products with better performance may not be obtained.