The viscous and the elastic properties of extrusion and injection grade low density polyethylenes(LDPE) were measured at three different temperatures. Viscosity for five LDPES tested exhibited the Newtonian behavior at low shear rates (below 0.1sec^-1). Introduction of the shift factor could eliminate the temperature dependency on viscosity, giving the master curve for viscosity. The elastic property represented by the first normal stress difference, recoverable shear strain or steady-state shear compliance was similar for five LDPES. Use of shear stress instead of shear rate made possible for us to compare the elasticity directly and to eliminate the temperature effect on elasticity. The melt index which is measured at a given temperature with a specified load is not suitable to relate with the processability.

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