The rheological properties of LLDPE can be summarized as "rigid in shear" and "soft in extension". When LLDPE is used to replace LDPE, the film extrusion equipment and conditions must be modified. The high viscosity of LLDPE requires the extruder to have higher power and provide higher melt temperature and pressure. The die gap must be widened to avoid production reduction due to high back pressure and melt fracture.