With the increase of the deformation rate of polyethylene, LDPE shows an amazing increase in viscosity, which is caused by molecular chain entanglement. This phenomenon cannot be observed in LLDPE, because the lack of long branched chains in LLDPE makes the polymer not entangled. This property is very important for thin film applications. LLDPE films are easier to make thinner films while maintaining high strength and toughness.

Although LLDPE and LDPE in the past belong to the same density range, their basic physical properties and molding processing characteristics are different due to their different molecular structures and melting rheological behaviors.