In the process of development, predecessor found that zinc oxide enhanced the activity of many vulcanizing agents, and gradually understood the action mechanism and mode of zinc oxide. In the vulcanization process, zinc oxide can react with vulcanizing agent, sulfur, stearic acid, rubber macromolecular chain and corresponding intermediates, indicating that the activation of zinc oxide is complex. However, a large number of test results show that zinc oxide, as a vulcanization active agent, mainly has an important impact on the formation rate, type and quantity of chemical crosslinking bonds in the vulcanization process, so as to improve the crosslinking degree of vulcanizate.

In the rubber compounding system, the compounding agent can be dissolved in the rubber compound, but the solubility of each compounding agent is different . With the change of temperature and dosage of compounding agent, some compounding agents will crystallize or spray out. Inorganic compounding agents generally exist in the compound in a dispersed state . Therefore, it can be considered that the reaction of zinc oxide as an active agent with agent, stearic acid, sulfur, etc. occurs on the surface of zinc oxide particles in the vulcanization process. Due to the high affinity of zinc oxide to electrons and absorb the electrons of vulcanizing agent, zinc salt soluble in rubber is formed under the action of stearic acid, so as to improve its solubility, and form a zinc complex with amine or fatty acid to make the vulcanizing agent active. Sulfur is added to the complex to form a vulcanizing agent by inducing activation.In this process, the surface of zinc oxide particles reacts continuously, the particle size decreases continuously, and zinc oxide is consumed until the rubber is fully vulcanized.

It can be considered that the traditional dosage is the dosage to fully activate vulcanization based on a specific zinc oxide particle size. With the change of ZnO particle size, its specific surface area and structure determine the activation of vulcanization.