1,3-Diphenylguanidine sulfate is primarily used as an accelerator in the vulcanization of rubber. It enhances the cross-linking process, improving the elasticity, durability, and mechanical properties of rubber products. This chemical is particularly effective in the production of tires, conveyor belts, and other industrial rubber goods, where high performance and resistance to wear are essential. Additionally, it is utilized in the synthesis of certain pharmaceuticals and as a stabilizer in polymer manufacturing. Its role in these applications ensures improved material performance and longevity.