According to the requirements of different properties of the final product, different vulcanization systems are used in the rubber formulation. Different curing systems have different curing characteristics. Some require a high activation temperature, and some require a low activation temperature. Therefore, the corresponding curing temperature should be selected according to the actual curing system. Generally, the ordinary sulfur vulcanization system has a vulcanization temperature selected from 130-160 ° C, which needs to be determined according to the active temperature of the accelerator used and the physical and mechanical properties of the product.

When the activation temperature of the accelerator is low or the product requires high strength, low elongation stress and hardness, the vulcanization temperature can be selected lower, so that more polysulfide crosslinks are generated; the activation temperature of the accelerator is higher or When the product requires high elongation stress and hardness, and lower elongation, the vulcanization temperature should be higher, which will generate more low-sulfur crosslinks.

For effective and semi-effective vulcanization systems, the vulcanization temperature is generally controlled between 160-165 ℃. For non-sulfur vulcanization systems such as peroxides and resins, the suitable vulcanization temperature is 170-180 ℃. In particular, for EPDM, NBR sulfur vulcanization Formulas, such as the design that require secondary vulcanization, the temperature and time of primary vulcanization and secondary vulcanization affect the mechanical properties of the final product such as compression set and hardness. The peroxide vulcanization formula requires a one-time vulcanization. The temperature is particularly important. The best temperature is above 180 ℃. If the temperature of the first sulfur addition is insufficient, the effect of the second sulfur addition is very low. That is, the peroxide vulcanization formula, the secondary sulfurization has little effect on the final physical properties.

Rubber is a poor conductor of heat and heats up slowly when heated. For thick products, it is difficult to make the inner and outer rubbers reach a flat range at the same time by high temperature vulcanization; when the outer part of the product is just vulcanized, the inner part is under-vulcanized. Or just when positive vulcanization occurs on the inside, and the vulcanization on the outside occurs. In order to ensure uniform vulcanization of thick products, in addition to the formulation's design, the vulcanization flatness of the rubber compound must be fully considered. When selecting the vulcanization temperature, the vulcanization temperature should be lower or a stepwise operation method should be adopted.

For thin products, the curing temperature can be appropriately high. For fabric-laminated rubber products, the vulcanization temperature is usually not higher than 140 ℃. For foamed rubber, the appropriate vulcanization temperature should be selected according to the decomposition temperature of the foaming agent and the foaming assistant.