IUPAC name
Polyethene or poly(ethylene)[1]
Other names
  • 9002-88-4 Y
Abbreviations PE
  • none
ECHA InfoCard 100.121.698
MeSH Polyethylene
Density 0.88–0.96 g/cm3[2]
Melting point 115–135 °C (239–275 °F; 388–408 K)[2]
log P 1.02620[3]
−9.67×10−6 (HDPE, SI, 22 °C)[4]
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references
The repeating unit within polyethylene in the most stable staggered conformation

Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most common plastic in use today. It is a polymer, primarily used for packaging (plastic bags, plastic films, geomembranes and containers including bottles, etc.). As of 2017, over 100 million tonnes of polyethylene resins are being produced annually, accounting for 34% of the total plastics market.[5][6]

Many kinds of polyethylene are known, with most having the chemical formula (C2H4)n. PE is usually a mixture of similar polymers of ethylene, with various values of n. It can be low-density or high-density: low-density polyethylene is extruded[verification needed] using high pressure (1000–5000 atm) and high temperature (520 kelvins), while high-density polyethylene is extruded[verification needed] using low pressure (6–7 atm) and low temperature (333–343 K). Polyethylene is usually thermoplastic, but it can be modified to become thermosetting instead, for example, in cross-linked polyethylene.