Linear Low Density Polyethylene / LLDPE

LLDPE is defined by a density range of 0.915-0.925 g/cm3. LLDPE is a substantially linear polymer with significant numbers of short branches, commonly made by copolymerization of ethylene with short-chain alpha-olefins (for example, 1-butene, 1-hexene and 1-octene). LLDPE has higher tensile strength than LDPE, it exhibits higher impact and puncture resistance than LDPE. Lower thickness (gauge) films can be blown, compared with LDPE, with better environmental stress cracking resistance but is not as easy to process. LLDPE is used in packaging, particularly film for bags and sheets.

Polymer Type

Thermoplastic

Advantages of LLDPE

Has higher tensile strength than LDPE.  Exhibits higher impact and puncture resistance than LDPE.  Lower thickness (gauge) films can be blown compared to LDPE, with better environmental stress cracking resistance compared to LDPE.

Disadvantages of LLDPE

Lower gloss than LDPE.  Narrower temperature range for heat sealing. Not as easy to process as LDPE.

Applications of LLDPE

Plastic Packaging - packaging film, plastic bags and flexible plastic sheets. Lower thickness (gauge) may be used compared to LDPE. Cable covering, toys, lids, buckets and containers, pipe.

Typical Properties of LLDPE

Property	Value
Density (g/cm3)	0.92
Surface Hardness	SD48
Tensile Strength (MPa)	20
Flexural Modulus (GPa)	0.35
Notched Izod (kJ/m)	1.06+
Linear Expansion  (/°C x 10 5)	20
Elongation at Break (%)	500
Strain at Yield (%)	20
Max. Operating Temp. (°C)	50
Water Absorption (%)	0.01
Oxygen Index (%)	17
Flammability UL94	HB
Volume Resistivity (log ohm.cm)	16
Dielectric Strength (MV/m)	25
Dissipation Factor 1kHz	0.0003
Dielectric Constant  1kHz	2.3
HDT @ 0.45 MPa (°C)	45
HDT @ 1.80 MPa (°C)	37
Material. Drying  hrs @ (°C)	NA
Melting Temp. Range (°C)	220 - 260
Mould Shrinkage (%)	3
Mould Temp. Range (°C)	20 -  60