Zinc oxide is an extremely versatile material being used in various industries and fields around the world. But one of the biggest users of zinc oxide is the rubber industry. This is because this material is irreplaceable for manufacturing various products of rubber. This is the importance of zinc oxide for rubber formulations.

Activating the Curing System

Zinc oxide would typically be added with stearic acid and together, they would form zinc soap. The combination of these two will improve the solubility of zinc oxide in rubber compounds. The formula of the accelerator then would form an element which is complex and able to produce a great vulcanizing agent when reacting with sulfur. 

Improving the Cross-linking Density

When zinc oxide is mixed together with stearic acid, it would form some kind of salt. This then would be chelated or mixed with a rubber accelerator which contains sulfur in it. Zinc oxide for rubber would strengthen the unstable bond and make it more stable by changing the sulfur bonds’ position. Because of this, the cross-linking density would be improved during the vulcanization process. 

Improving Anti-aging Properties

In the process of vulcanization for rubber, the bond of polysulfide would break. This would result in H2S which then would accelerate the process of deterioration such as cracking. This is why zinc oxide would play its key role because it would react with the H2S in rubber compounding in order to form new bonds of cross-linking.

The use of zinc oxide for rubber vulcanization process would stabilize the process itself and therefore, improve the rubber products’ anti-aging properties. This is why zinc oxide is extremely important for the manufacturing of rubber products because this material would enhance their lifespan, improving performance, and also enhancing the safety standards.