During the mixing process, the mixing materials are likely to change their properties and produce toxicity and stinking gas. Therefore, shaft seals are needed for hermetic containers to make them airtight and leakage proof. Especially in the field of pressurized containers, shaft seal is a very important key. Based on pressure value, rotating speed of the main shaft, raw material property etc, there are different designs and requirements for mechanical structure and material selection. The commonly used shaft seals include rubber shaft seal, Gland shaft seal and mechanical shaft seal, which can be single layered or multiple layered or composite based on the condition and requirements. Selection of shaft seal should consider the material property, temperature, rotating speed of the mixing shaft etc and provide protective measures including cooling, lubrication, anti-wear and anti-corrosion for the materials.