Rheological behavior of blends of poly (ethylene-acrylic acid) (EAA) and ethylene vinyl acetate (EVA) copolymer have been carried out at various temperatures, namely, 100, 110, and 120 degrees C, and different shear rates from 61.33 to 613.30 s(-1) using a Monsanto Processability Tester. The melt viscosity of the blends shows synergism during processing. The activation energy of the blends is in the range 20.7-44.6 kJ/mol. Highest activation energy was observed for the blends containing 40 - 60% of EVA by weight. (c) 2005 Wiley Periodicals, Inc.