HMWPE, HDPE/PE-HD (High molecular weight, high density polyethylene )

Designation

High molecular weight, high density polyethylene / HMWPE / HDPE

Tradenames

Accucomp, Alathon, Alcudia, Arak, Asrene, Axeleron, Bapolene, Borcell, Borcoat, Borealis, Bormed, Borpex, Borsafe, Borstar, Bretene, Certene, Colorrx, Continuum, Daelim, Delta, Dow Health+, Dowlex, Egyptene, Eleme, El-Lene, Eltex, Eraclene, Etilinas, Evalene, Evolue-H, Exelene, Formolene, G-Lene, G-Lex, Halene, Hanwha, Hiplex, Hival, Hivorex, Hi-Zex, Hostalen, Hypel, Icorene, Indothene, Ineos, Innoplus, J-Rex, Kazan, Kemcor, Lanufene, Lumicene, Lupolen, Lutene, Marflex, Marlex, Marpol, Midilena, Mtegrity, Neftekhim, Nexus, Novapol, Novatec, Paxon, Petilen, Petrothene, Plexar, Polimaxx, Polycompo, Ponacom, Primatop, Prixene, Purell, Qenos, Quadrant, Ravago, Relene, Rigidex, Sabic Vestolen, Safrene, Samsung Total, Sclair, Seetec, Snolen, Surespec, Surpass, Taborex, Taisox, Tipelin, Titanex, Titanvene, Titanzex, Toler, Total, Unilex, Unithene, Unival, Venelene, Vestolen, Yanshan, Yuclair, Yuhwa, Yuzex

Typical uses

Pipes, toys, bowls, buckets, milk bottles, crates, tanks, containers, film for packaging, blown bottles for food.

Compositional summary

(CH2-CH2)n

Material family	Plastic (thermoplastic, semi-crystalline)
Base material	PE-HD (Polyethylene, high density)
Polymer code	PE-HD

Composition detail

Polymer

100

Physical properties

Density

0.947

–

0.955

g/cm³

Mechanical properties

Young’s modulus	0.915	–	0.961	GPa
Specific stiffness	0.962	–	1.01	MN.m/kg
Yield strength (elastic limit)	19.3	–	26.9	MPa
Tensile strength	17.2	–	29.6	MPa
Specific strength	20.3	–	28.3	kN.m/kg
Elongation	170	–	800	% strain
Compressive modulus	0.915	–	0.961	GPa
Compressive strength	23.2	–	32.3	MPa
Flexural modulus	0.859	–	1.2	GPa
Flexural strength (modulus of rupture)	24.1	–	41.4	MPa
Shear modulus	0.322	–	0.338	GPa
Bulk modulus	1.94	–	2.04	GPa
Poisson’s ratio	0.413	–	0.43
Shape factor	4.8
Hardness – Vickers	6	–	8	HV
Hardness – Rockwell M	31	–	35
Hardness – Rockwell R	45	–	55
Elastic stored energy (springs)	203	–	377	kJ/m³
Fatigue strength at 10^7 cycles	8	–	11	MPa

Impact & fracture properties

Fracture toughness	1.14	–	2.09	MPa.m^0.5
Toughness (G)	1.48	–	4.34	kJ/m²
Impact strength, notched 23 °C	76.2	–	84	kJ/m²
Impact strength, notched -30 °C	57.1	–	63	kJ/m²
Impact strength, unnotched 23 °C	590	–	600	kJ/m²
Impact strength, unnotched -30 °C	590	–	600	kJ/m²

Thermal properties

Melting point	125	–	135	°C
Glass temperature	-125	–	-90	°C
Heat deflection temperature 0.45MPa	68	–	70	°C
Heat deflection temperature 1.8MPa	29	–	60	°C
Maximum service temperature	110	–	130	°C
Minimum service temperature	-82	–	-72	°C
Thermal conductivity	0.191	–	0.198	W/m.°C
Specific heat capacity	1.75e3	–	1.81e3	J/kg.°C
Thermal expansion coefficient	126	–	198	µstrain/°C
Thermal shock resistance	117	–	202	°C
Thermal distortion resistance	9.81e-4	–	0.00154	MW/m

Electrical properties

Electrical resistivity	3.3e24	–	3e25	µohm.cm
Electrical conductivity	5.75e-24	–	5.22e-23	%IACS
Dielectric constant (relative permittivity)	2.2	–	2.4
Dissipation factor (dielectric loss tangent)	4e-4	–	6e-4
Dielectric strength (dielectric breakdown)	19.7	–	23.6	MV/m
Comparative tracking index	600			V

Magnetic properties

Magnetic type

Non-magnetic

Optical, aesthetic and acoustic properties

Refractive index	1.53	–	1.55
Transparency	Translucent
Acoustic velocity	981	–	1010	m/s
Mechanical loss coefficient (tan delta)	0.0416	–	0.0437

Absorption & permeability

Water absorption @ 24 hrs	0.005	–	0.01	%
Water vapor transmission	0.0283	–	0.0425	g.mm/m².day
Permeability (O2)	49.8	–	69.4	cm³.mm/m².day.atm

Processing properties

Polymer injection molding	Excellent
Polymer extrusion	Excellent
Polymer thermoforming	Acceptable
Linear mold shrinkage	1.5	–	4	%
Melt temperature	191	–	246	°C
Mold temperature	30	–	50	°C
Molding pressure range	82.5	–	103	MPa

Durability

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