• Melting Point: —115 °C

• Crystallinity: Low crystallinity (50-60% crystalline). Main chain contains many side chains of 2-4 carbon atoms leading to irregular packing and low crystallinity (amorphous).

• Strength: Not as strong as HDPE due to irregular packing of polymer chains.

• Transparency: Good transparency, since it is more amorphous (has noncrys­talline regions) than HDPE.

• Density: 0.91-0.94 g/cm3, lower density than HDPE.

• Chemical properties: Chemically inert. Insolvent at room temperature in most solvents. Good resistance to acids and alkalis. Exposure to light and oxygen results in loss of strength and loss of tear resistance.

• Tensile elongation at rupture (%): 906.

15.1.2.3 APPLICATIONS

Low-density polyethylene (LDPE) is used mainly in film applications for both pack­aging and nonpackaging applications (Fig. 15.3). Other markets include extrusion coatings, sheathing in cables and injection molding applications. LDPE is the oldest and most mature of the polyethylenes (PEs). It is characterized by its short and long chain branching, which gives it good clarity and processability although it does not have the strength properties of the other PEs.

FIGURE 15.3 LDPE application.