Linear low density polyethylene

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Linear low density polyethylene (LLDPE) is a substantially linear polymer, with significant numbers of short branches, commonly made by copolymerization of ethylene with longer-chain olefins.

LLDPE has higher tensile strength and higher impact and puncture resistance than LDPE. It is very flexible and elongates under stress. It can be used to make thinner films, with better environmental stress cracking resistance. It has good resistance to chemicals and to ultraviolet radiation. It has good electrical properties. However it is not as easy to process as LDPE, has lower gloss, and narrower range for heat sealing.

It is used for plastic bags and sheets (where it allows using lower thickness than comparable LDPE), plastic wrap, pouches, toys, lids, pipes, buckets and containers, covering of cables, geomembranes, and mainly for flexible tubing.

LLDPE manufactured using metallocene catalysts is labeled mLLDPE.

[edit] Physical Properties

Property	Value
Density	0.92 g/cm³
Surface hardness	SD48
Tensile strength	20 MPa
Flexural modulus	0.35 GPa
Notched izod	1.06+ kJ/m
Linear expansion	20×10−5/°C
Elongation at break	500%
Strain at yield	20%
Max. operating temp.	50 °C
Water absorption	0.01%
Oxygen index	17%
Flammability UL94	HB
Volume resistivity	log(16) Ω·cm
Dielectric strength	25 MV/m
Dissipation factor 1kHz	909090
Dielectric constant 1kHz	2.3
HDT @ 0.45 MPa	45 °C
HDT @ 1.80 MPa	37 °C
Material drying	NA
Melting Temp. Range	120 to 160 °C
Mould Shrinkage	3%
Mould temp. range	20 to 60 °C

See also:

• Low density polyethylene
• High density polyethylene
• Ultra high molecular weight polyethylene