The tensile strength of rubber is the ultimate ability of rubber products to resist tensile failure. It is one of the important indicators of rubber products. The life of many rubber products is directly related to tensile strength.

1. Tensile strength is related to the molecular structure of rubber. All other factors that affect intermolecular forces have an effect on tensile strength. When the molecular weight is smaller, the secondary bonds of intermolecular interactions are smaller. When the external force is greater than the intermolecular action, intermolecular sliding will occur and the material will be destroyed. On the contrary, if the molecular weight is large, the intermolecular force increases, the cohesion of the rubber compound increases, the chain segment is not easy to slide during stretching, and the degree of damage to the material is small.

2. Reinforcing agent is one of the important factors affecting tensile strength. The smaller the diameter of the filled material, the larger the specific surface area, the larger the surface activity, the higher the structure, and the better the reinforcement performance.

3. Different softeners have different degrees of reduction in tensile strength. Adding softener will reduce the tensile strength, but adding a small amount, generally less than 7 parts in the open kneader, and less than 5 parts in the compact mixer will improve the dispersion, which is beneficial to improve the tensile strength.

4. Tensile strength is also related to temperature. The tensile strength at high temperature is much lower than that at room temperature.

5. The tensile strength is related to the crosslinking density. With the increase of cross-linking density, the tensile strength increases, and after the maximum value appears, the tensile strength will decrease significantly.