General Properties
Short Name: PE-LD
Name: Polyethylene Low DensityThe mass density is defined as the ratio between mass and volume. Density
Polyethylene low DensityThe mass density is defined as the ratio between mass and volume. density (PE-LD) consists of extensively branched polymer chains and therefore has a low DensityThe mass density is defined as the ratio between mass and volume. density. It is produced from ethylene under high pressure and belongs to the groups of polyolefins. Based on the volume produced, PE-LD is the most important plastic of all.
Structural Formula
Properties
NETZSCH Measurement
| Sample Mass | 12.11 mg |
| Heating Rates | 10 K/min |
| Crucible | Al, pierced lid |
| Atmosphere | N2 (40 ml/min) |
Evaluation
A characteristic feature of this polymer is that the melting transition – as in the present case – can start very early (here at approx. 40°C). The peak temperatures of the endothermal melting effects are at 112/113°C (1st heating, blue and 2nd heating, red) and are therefore relatively high for PE-LD. The shoulder in the melting eff ect in the 1st heating (blue) is absent in the 2nd heating (red). It can be concluded from this observation that stresses in the material (thermomechanical history) were eliminated during the 1st heating. The Glass Transition TemperatureThe glass transition is one of the most important properties of amorphous and semi-crystalline materials, e.g., inorganic glasses, amorphous metals, polymers, pharmaceuticals and food ingredients, etc., and describes the temperature region where the mechanical properties of the materials change from hard and brittle to more soft, deformable or rubbery.glass transition of polyethylene is generally small (small Δcp, i.e., changes in the specific heat level prior to and after the effect) and therefore sometimes hard to detect by DSC.