Ethylene propylene diene monomer (EPDM) is polymerized by adding a small amount of non conjugated dienes to ethylene and propylene monomers. The characteristic of its structure is that there is no unsaturated double bond in the main chain of the polymer molecule, but there is unsaturated double bond in the branch chain.

Therefore, it has excellent weather resistance, heat resistance, ozone resistance, UV resistance, good processability and low compression permanent deformation. It is the preferred material for the production of sealing strips.

At present, the vast majority of automotive sealing strip materials use EPDM as the main raw material; EPDM has excellent ozone resistance and is also known as "crack free rubber". Especially when it is used in various urban buildings with different atmospheric indexes and completely exposed to the air, it will show the superiority of its products; Anti ultraviolet radiation provides environmental protection for residents of high-rise buildings; Voltage resistance, corona resistance, electric cracking resistance and arc resistance are also excellent.