LLDPE for injection molding has a large ratio of tensile properties to LDPE properties, and the tensile amount and tensile yield strength, especially tensile breaking strength and elongation at break, are large. Generally, the energy required for fracture can be calculated from the area of stress-strain curve as an index of resin rigidity. Obviously, LLDPE has good rigidity, which can be considered as a result of a large number of chain molecules in LLDPE molecules.

Relationship between rigidity and density: The lower the density, the worse the rigidity (that is, the softer). In terms of the same density, LLDPE has higher impact strength, while C6 and C8*** polymers with more monomers than C4 have higher impact strength.

The physical and mechanical properties of LLDPE film are obviously better than LDPE, and its softness, toughness, cold resistance and puncture resistance are all better than LDPE.