High density polyethylene (HDPE) is a white powder or granular product. Non toxic, tasteless, crystallinity 80% ~ 90%, softening point 125 ~ 135 ℃, service temperature up to 100 ℃; Hardness, tensile strength and creep are better than those of low density polyethylene; Good wear resistance, electrical insulation, toughness and cold resistance; Good chemical stability, insoluble in any organic solvent at room temperature, resistant to acid, alkali and various salts.
The film has low permeability to water vapor and air and low water absorption; The aging resistance is poor, and the environmental stress cracking resistance is not as good as that of low-density polyethylene. In particular, thermal oxidation will degrade its performance. Therefore, antioxidants and ultraviolet absorbers must be added to the resin to improve this deficiency. The thermal deformation temperature of HDPE film under stress is low, which should be paid attention to in application.
