The mechanical sealing material is the basis of its existence and development. Friction auxiliary in high speed rotation of Chinese medicine resistance medium corrosion, under a certain pressure, heat exchange. The task of sealing with relative motion and friction, thus creating some requirements for the material.

1. In corrosion prevention to have good chemical stability, can resist the medium corrosion, abrasion, dissolution and swelling;
2. In terms of physical and mechanical properties, there should be high elastic modulus, strength and allowable pv value, low friction coefficient and line expansion coefficient, excellent wear resistance and self-lubrication, and good impermeability;
3. In terms of thermal performance to have good thermal conductivity, heat resistance, cold resistance and temperature resistance of rapid degeneration;
4. Convenient material source, easy processing and manufacture, low cost.