High-density polyethylene (HDPE) is a semi-crystalline thermoplastic material. The appearance of the original HDPE is milky white, and the thin section is translucent to a certain extent. The polymer is non-hygroscopic and has good water vapor resistance, making it useful for packaging applications. HDPE plastic bottles are a popular packaging choice in the milk and fresh juice market.

HDPE has good electrical properties, especially the high dielectric strength of the insulation, which is very suitable for wires and cables. Medium to high molecular weight grades of HDPE have excellent impact resistance at room temperature and even at temperatures as low as -40F. The unique characteristics of the various grades of HDPE are the proper combination of the four basic variables of density, molecular weight, molecular weight distribution and additives. These variables combine to produce HDPE grades for different uses, achieving an optimal balance of properties.