This work describes the preparation, characterization, and evaluation of the oxygen permeability of blends based on a polyolefin synthesized with a metallocene catalyst (ethylene/1-octene copolymer) and a vinyl alcohol/ethylene copolymer in an attempt to establish the corresponding relationships between the composition, morphology, and transport properties to design materials with optimized and enhanced agricultural and food packaging performances. Moreover, microhardness measurements have been used to analyze the mechanical response of these blends and to obtain information about the dispersion of the two immiscible components within the blends. (C) 2004 Wiley Periodicals, Inc.