The difference between EPDM rubber and Silicone rubber

What are the differences between EPDM rubber and silicone rubber? First of all, EPDM rubber is a terpolymer of ethylene, propylene and non-conjugated diene. Diene has a special structure, and only one of the two bonds can be copolymerized, and the unsaturated double bond is mainly used as a cross-chain. The other unsaturated one will not become the main polymer chain, only the side chain. The main polymer chain of EPDM is fully saturated. This feature makes EPDM resistant to heat, light, oxygen, and especially ozone. EPDM is essentially non-polar, has resistance to polar solutions and chemicals, has low water absorption, and has good insulation properties.

Silicone rubber is classified into two types: hot vulcanized silicone rubber and room temperature vulcanized silicone rubber according to its vulcanization characteristics. According to the performance and use, it can be divided into general type, ultra low temperature resistant type, ultra high temperature resistant type, high strength type, oil resistant type, medical type and so on. According to the different monomers used, it can be divided into methyl vinyl silicone rubber, methyl phenyl vinyl silicone rubber, fluorosilicone, nitrile silicone rubber, etc.

However, silicone rubber has excellent heat resistance, cold resistance, dielectric properties, ozone resistance and atmospheric aging resistance. The outstanding performance of silicone rubber is that it can be used at a wide temperature range from -60°C (or lower temperature) to Long-term use at +250°C (or higher temperature).

However, silicone rubber has poor mechanical properties such as tensile strength and tear strength. Its physical and mechanical properties are not as good as most synthetic rubbers at room temperature. In addition to nitrile silicone and fluorosilicone rubber, general silicone rubber is resistant to oil and solvents. The performance is not good, so silicone rubber is not suitable for occasions under ordinary conditions, but it is very suitable for many specific purposes.