This study examines the linear viscoelastic properties and processing of blends of a metallocene polyethylene with different ultrahigh molecular weight polyethylenes (UHMWPEs). Blend compositions were prepared such that they were below and above the UHMWPE coil overlap concentration, c*. Linear rheology and processing were found to be very sensitive to molecular weight and concentration, suggesting an effective macromolecular network threshold. The linear viscoelastic behavior of the blends could be described using a simple model based on reptation, implying a segmental interaction of the macromolecules. Extrusion flow curves were identical for the pure material and blends. However, for a given blend composition, the amplitude of the sharkskin distortion diminished as the UHMWPE molecular weight in the blend increased, and completely vanished at a value corresponding to the coil overlap condition. For a given molecular weight of the UHMWPE, it was also possible to obtain distortion free extrudates simply by maintaining the UHMWPE concentration above the corresponding c*. (C) 2011 The Society of Rheology. [DOI: 10.1122/1.3589798]