Improve the tensile strength and elongation of rubber products, high tensile strength formulations using natural rubber products, neoprene products, chlorinated yellowing polyethylene rubber products and other crystalline rubber. The rate of rubber content can reach 60% to about. In addition, the use of excellent reinforcing filler such as carbon black, silica and make it evenly dispersed. When using silica, the dosage should not exceed 25 parts, when using non-crystalline rubber to increase the amount of reinforcing agent, pay attention to uniform dispersion and the use of faster vulcanization system. 1. Reduce the amount of sulfur yellow, more softeners or plasticizers can be used to obtain elongation of rubber products. Promoter selection of thiazole, the dosage should be increased to maintain the flat performance of sulfur vulcanization curve, filler less added. To use clay is better, can also use carbon black, especially soft carbon black. Factors affecting the strength of rubber products are many, in addition to the crosslinking density of the main factors are as follows
　　1. deformation speed, strength time-dependent is a common law of all materials, in the rapid application of force, the strength of rubber products to be higher than the slow, because the rapid application of force when the molecular chain is too late to stretch, the chain is still under tension and thus the chance of fracture is reduced, the strength increases. 
　　2. elongation crystallinity, non-crystalline rubber products formula strength is low, elongation crystallization of natural rubber products, choose the appropriate vulcanization system, the strength can reach 250 kg / cm or so. This is because the natural rubber products with the increase in elongation, crystallization in the direction of stretching, natural rubber products crystallization takes about 2 seconds or more short of some time, in high-speed test conditions do not show the reinforcing effect. 
　　3. Temperature, the tensile strength measured at different temperatures have differences. Synthetic rubber, especially the greater polarity of rubber products at low temperatures have a high tensile strength, tensile strength at high temperatures is low, the use of reinforcing agents can improve the strength, but still not as good as natural rubber vulcanized products. In order to improve this shortcoming. Can be used in synthetic rubber products can be introduced to produce chemical cross-linking of functional groups, through the formation of the main valence bonding method, or make the structure of the chemical structure with active hydrogen atoms, the use of reactive halogens to increase cross-linking, etc. to improve the strength of rubber products.
　　4. Molecular weight, strength increases with the increase in molecular weight, this is because when the molecular chain is long, the intermolecular force is large, the flexibility of the molecular chain is relatively larger, such as polar substituents on the molecular chain, so that the secondary price increases, the strength will also increase. 
　　5. branched and gel, in the polymerization process or in the high temperature strong mechanical action can make rubber rubber products molecules produce branched chain, by the presence of branched chain so that the irregular arrangement of macromolecules, vulcanization of rubber products after the mesh structure is incomplete, may produce cracks, so that the strength is reduced. The gel produced in the polymerization process also destroys the regularity of rubber molecules, so that the rubber products manufacturer strength is reduced.