High density polyethylene (HDPE) is non-toxic, tasteless, no smell white particles, it is mainly a linear molecular structure and has little branching. It has a high degree of crystallization and high density,melting point is about 130°C, relative density of 0.941 – 0.960. It has good heat resistance and cold resistance, chemical stability, but also has high rigidity and toughness, good mechanical strength. Dielectric properties, environmental stress cracking resistance are also good.