Potentially reactive blends of styrene-maleic anhydride (SMAH) with ethylene/methyl acrylate/glycidyl methacrylate (E-MA-GMA) and nonreactive blends of SMAH with ethylene/methyl acrylate (E-MA) were produced in a Brabender batch mixer and in a corotating twin-screw extruder. The products were characterized in terms of rheology, morphology, and mechanical properties to understand the reaction characteristics between anhydride/epoxy functional groups. Storage modulus, G', loss modulus, G" and complex viscosity, eta* of the reactive blends were higher than those of nonreactive ones. At 25% E-MA-GMA content, maximum in eta* was obtained for the reactive blends. The reactive blends showed finer morphology than the nonreactive ones at all concentrations studied. Mechanical characterization showed that reactive SMAH/E-MA-GMA blends had higher tensile strength, % strain at break, and tensile modulus than the nonreactive blends for all corresponding modified polyethylene contents. (C) 2001 John Wiley & Sons, Inc.