Rheological properties and foam processability for blends of linear and crosslinked polyethylenes

The effect of blending crosslinked linear low‐density polyethylene (cLLDPE) on the rheological properties and foam processability of linear low‐density polyethylene was studied. A small addition of cLLDPE, which had a low density of crosslink points, enhanced strain‐hardening behavior in the elongational viscosity to a great degree, although it had little effect on the steady‐state shear viscosity. The enhanced strain hardening reduced heterogeneous deformation during foaming. As a result, a foam with a uniform cell size distribution was obtained.