Polyethylene HDPE/PE300 (extruded) is similar to PE500 (pressed) but has higher rigidity and lower impact/shock resistance. Chemical resistance is good. PE300 is less expensive and is available in both rod and sheet form. Operating temperature range is -50°C to +90°C.
Chemical: high chemical resistance typical of the polyolefins.
Shock resistance, good even at low temperature.
High abrasion resistance.
Low friction coefficient.
Low specific gravity.
Colour: natural and black
POLYETHYLENE WEAK POINT
Compared to the engineering plastics it has lower thermal and mechanical properties: tensile stress, flexural and compressive strength, etc. Compared to high molecular weight PE, it is more rigid and its resistance to continuous shock is therefore lower.
Mechanical: The low friction coefficient and its non hygroscopicity make it suitable for use as a bearing or mechanical parts with low loads, even when operating in water.
Food contact: physiologically inert, it is approved for food contact by the most important standards organisations. Thanks to this feature, it is widely used for components in food machinery, pumps for liquid food etc.
Electrical: very good dielectric properties, weatherproof.
Chemical: thanks to the high resistance to acids and alkali it is used for components in the chemical industry.
The graph shows that the PE with higher molecular weights have a higher shock resistance, whilst their tensile stress is lower.
Blue: shock resistance
Yellow : tensile stress