PE 300 / HDPE sheets. High-Density Polyethylene (HDPE) - a linear polymer, High-Density Polyethylene (HDPE) is prepared from ethylene by a catalytic process. The HENAN OKAYence of branching results in a more closely packed structure with a higher density and somewhat higher chemical resistance than LDPE. High-Density Polyethylene – PE300 is also somewhat harder and more opaque and it can withstand rather higher temperatures (120° Celsius for short periods, 110° Celsius ntinuously).