Steady‐state flow curves were obtained on a series of polyethylene‐wax blends over a shear rate range of 10−2
to 10+3 sec−1.
Wax concentration extended from 0 to 85%. The wax was a low molecular weight polyethylene (w = 5400
and w/n = 1.54
). Seven polyethylenes with melt indices ranging 0.3 to 9 and w/n
ranging from 3 to 15 were examined. Included in the samples were homopolymers, copolymers with a small amount of short branches, copolymers with a small amount of short and long branches, and low density polyethylene. Concentration superpossability was demonstrated with these samples. For the high molecular weight polymers, superposition provided a means of estimating the low shear Newtonian viscosity, η0,
which could not be directly measured. Values of η0
were compared to w
obtained by GPC. The effects of branches on the concentration shift factors for superposition were discussed.