الوصف

HDPE is known for its large strength to density ratio. The mass density of high-density polyethylene can range from 0.*3 to 0.*7 g/cm3. Although the density of HDPE is only marginally higher than that of low-density polyethylene, HDPE has little branching, giving it stronger intermolecular forces and tensile strength than LDPE. The difference in strength exceeds the difference in density, giving HDPE a higher specific strength. It is also harder and more opaque and can withstand somewhat higher temperatures (**0 °C/ **8 °F for short periods, **0 °C /**0 °F continuously). High-density polyethylene, unlike polypropylene, cannot withstand normally required autoclaving conditions. The lack of branching is ensured by an appropriate choice of catalyst(e.g., Ziegler-Natta catalysts) and reaction conditions.