Polyethylene Medium Density Material Data Sheet (molding and extrusion)

Designation

Medium density polyethylene / MDPE (medium density, branched homopolymer)

Tradenames

AEI, Alathon, AXELERON, Borealis PE, BorSafe, Borstar, CERTENE, CONTINUUM, DOW MDPE, Eltex, Epolene, Ethylplus, ETILINAS, FINGERPRINT, Formolene, HIPLEX, INEOS HDPE, INEOS Wire & Cable, Kazan MDPE, Kemcor, KW Plastics, LITEN, Lumicene, Marlex, MARPOL® MD, Moharamplast MDPE, NEFTEKHIM PE, Petrothene, Qenos PE, Ravago Compounds, Ravalene, RECLAIR, SCLAIR, TIPELIN, Titanvene, TOTAL PETROCHEMICALS Polyethylene, Trithene, VENELENE, YUCLAIR

Typical uses

Packaging, Piping, Wire & cable jacketing, Film, Tanks, Bags, General Purpose, Industrial applications, Liners, Fittings, Containers, Food packaging, Electrical and Electronical, Blending, Automotive, Outdoor applications, Toys, Shrink wrap, Adhesives, Pipe coatings, Natural gas distribution, Building materials, Laminates, Chemical Process, Household goods, Blow molding applications, Bottles, Caps

Compositional summary

(CH2-CH2)n
Material family	Plastic (thermoplastic, semi- crystalline)
Base material	PE-MD (Polyethylene, medium density)
Polymer code	PE-MD

Composition detail

Polymer

100

Physical properties

Density

0.931

–

0.946

g/cm³

Mechanical properties

Young’s modulus	0.75	–	0.8	GPa
Specific stiffness	0.798	–	0.853	MN.m/kg
Yield strength (elastic limit)	16	–	20	MPa
Tensile strength	27.5	–	33	MPa
Specific strength	17	–	21.3	kN.m/kg
Elongation	500	–	800	% strain
Elongation at yield	9	–	15	% strain
Compressive strength	15	–	22	MPa
Flexural modulus	0.65	–	0.73	GPa
Flexural strength (modulus of rupture)	15	–	19.3	MPa
Hardness – Shore D	53	–	63
Elastic stored energy (springs)	167	–	256	kJ/m³
Fatigue strength at 10⁷cycles	11.5	–	12.7	MPa

Impact & fracture properties

Impact strength, notched 23 °C	40	–	65	kJ/m²
Impact strength, notched -30 °C	5	–	8	kJ/m²
Impact strength, unnotched 23 °C	590	–	600	kJ/m²
Impact strength, unnotched -30 °C	590	–	600	kJ/m²

Thermal properties

Melting point	123	–	127	°C
Glass temperature	-273	–	-75	°C
Heat deflection temperature 0.45MPa	51.6	–	64.1	°C
Heat deflection temperature 1.8MPa	35	–	43	°C
Vicat softening point	106	–	121	°C
Thermal conductivity	0.48			W/m.°C
Specific heat capacity	2300			J/kg.°C
Thermal expansion coefficient	50	–	150	µstrain/°C
Thermal shock resistance	153	–	465	°C
Thermal distortion resistance	0.0032	–	0.0096	MW/m

Electrical properties

Electrical resistivity	1e21	–	1e22	µohm.cm
Electrical conductivity	1.72e-20	–	1.72e-19	%IACS
Dielectric constant (relative permittivity)	2.3	–	2.5
Dissipation factor (dielectric loss tangent)	4e-4	–	0.001
Dielectric strength (dielectric breakdown)	20	–	22	MV/m

Magnetic properties

Magnetic type

Non-magnetic

Optical, aesthetic and acoustic properties

Transparency	Translucent
Acoustic velocity	893	–	924	m/s

Absorption & permeability

Water absorption @ 24 hrs

0.02

Processing properties

Polymer injection molding	Excellent
Polymer extrusion	Excellent
Polymer thermoforming	Acceptable
Linear mold shrinkage	3.3			%
Melt temperature	210	–	250	°C

Durability

Water (fresh)	Excellent
Water (salt)	Excellent
Weak acids	Excellent
Strong acids	Acceptable
Weak alkalis	Acceptable
Strong alkalis	Acceptable
Organic solvents	Limited use
Oxidation at 500C	Unacceptable
UV radiation (sunlight)	Poor
Flammability	Highly flammable