Linear Low Density Polyethylene (LLDPE)

Linear Low Density Polyethylene:

Linear low-density polyethylene is shortly known as LLDPE. LLDPE is a substantially linear polymer (polyethylene), with significant numbers of short branches, commonly made by copolymerization of ethylene with longer-chain of olefins. Linear low-density polyethylene differs structurally from predictable low-density polyethylene (LDPE) because of the absence of long chain branching.


Processing & Properties:

LLDPE has a unique melt flow properties. LLDPE is less shear sensitive because of its narrower molecular weight distribution and shorter chain branching. During a shearing process, such as extrusion, LLDPE remains more viscous than LDPE. The lower shear sensitivity of LLDPE allows for a faster stress relaxation of the polymer chains during extrusion, and, therefore, the physical properties are susceptible to changes in blow-up ratios. In melt extension, LLDPE has lower viscosity at all strain rates. As the deformation rate of the polyethylene increases.

Physical Properties:

Properties Nominal Values
Density 0.88 – 0.915 gm/cc
Tensile Strength 30 MPa
Flexural Modulus 0.35 GPa
Izod Impact (Notched) 1.06 KJ/M
Elongation at Break 400%
Heat Distortion Temp. (Load@ 1.80 MPa) 37 Deg C
Flammability UL94 HB
Melting Temperature 130-160 Deg C
Mould Shrinkage Max. 3%
Mould Temperature 20-60 Deg C
Operating Temperature Max. 50 Deg C
Water Absorption 0.01 %
Oxygen Index Max. 17%

 



Uses:

it is used for plastic bags and sheets, plastic wrap, stretch wrap, pouches, toys, covers, lids, pipes, buckets and containers, covering of cables, geomembranes & flexible tubes.

 

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