High density polyethylene (HDPE) is the largest of the three polyethylenes (PE) by volume of consumption. It has a very linear structure with only a few short side branches leading to a higher density range as well as a more crystalline structure. It is defined by a density of greater or equal to 0.941 g/cm3. HDPE has a low degree of branching and thus stronger intermolecular forces and tensile strength.
A linear polymer, High Density Polyethylene (HDPE) is prepared from ethylene by a catalytic process. The absence of branching results in a more closely packed structure with a higher density and somewhat higher chemical resistance than LDPE. HDPE is also somewhat harder and more opaque and it can withstand rather higher temperatures (120