About High Density Polyethylene (HDPE)
High Density Polyethylene (HDPE), also known as sandwich board, is a thermoplastic derived from petroleum hydrocarbons.
It is the world’s most widely used plastic, with a production rate of around 80 million metric tons annually.
Key characteristics include toughness, light weight, high wear resistance, good resistance to corrosion and chemicals, and easy machinability.
Key Properties
| General | |
|---|---|
| Density relative to water (=1) | 0.94 |
| Water absorption (24 hrs) | 0.03% |
| Thermal | |
|---|---|
| Continuous Service Temperature | 75°C (167°F) |
| Melting point | 125°C (257°F) |
| Mechanical | |
|---|---|
| Tensile Modulus of Elasticity | 800 N/mm2 |
| Elongation at Break | 500% |
| Yield Stress | 22 N/mm2 |
| Impact Strength, Notched Izod @ 23°C | 13 kJ/m2 (6.2 ft-lbs/in2) |
Download datasheet (123Kb)
Applications
In addition to packaging and storage, HDPE is used for the following:
- Concreting: HDPE is used in concreting as a protection liner. The natural colour aids the cooling process for large projects by allowing the concrete to cool more slowly, forming a stronger finish.
- Sliding: A HDPE coating is used to help material slide across a surface more efficiently
- Wear Pads: HDPE is used to protect metal and other surfaces from friction damage, such as turntables on semi-trailers
- Construction: Uses in construction include roof window frames and wash basins
- Motor vehicles: HDPE is used in car trunk linings, motorbike mudflaps, seats and wheel arches
- Household: HDPE is most commonly known as cutting board material, and is used in homes to cut bread and other food items
- Fishing: HDPE is used by fishermen as bait board material
- Boating: HDPE is used to roll or slide boats on and off trailers, and as a packing panel behind the motor to save having to drill into the structure of the boat. HDPE panels are also used for their light weight as a finishing plastic on boats
Other uses of HDPE include shopping bags, pallets, piping, battery cells, drip trays, fans and etching baths.
History
1898 – Polyethylene is synthesised by accident by German chemist Hans von Pechmann while he is heating diazomethane
1935 – The first solid form of polyethylene is created by British chemists Eric Fawcett and Reginald Gibson by working with ethylene at high pressure
1953 – High density polyethylene (HDPE) is created at the Kaiser Wilhelm Institute by Karl Ziegler and Erhard Holzkamp
1955– The first HDPE pipe is produced
