Control on the morphology-processing-properties relationships of polyolefin/organoclay nanocomposites is paramount for food packaging applications. This research reports the influence of the intermolecular interactions between ethylene vinyl acetate copolymer (EVA) and ethylene vinyl alcohol copolymer (EVOH) each with organically modified montmorillonite (MMT) on the morphology, mechanical and barrier properties of polypropylene (PP) based films. PP/EVA and PP/EVOH (75/25%wt) blends were reinforced with 1, 3 and 5%wt MMT (introduced via a polypropylene grafted maleic anhydride) in a double screw internal mixer. Four different copolymers (EVA12%, EVA28% co-monomer content of vinyl acetate (VA), EVOH32%, and EVOH44% molar content of vinyl alcohol (OH)) were used to prove that a higher amount of favorable intermolecular interactions with MMT is obtained with higher content of VA or OH functional groups of the copolymer. Samples were compression-molded into films of 300μm. The structural characterization was made using X-ray diffraction, mechanical properties were characterized with simple tension essay, and oxygen permeation by oxygen transmission rate (OTR). XRD patterns showed a combination of intercalated/exfoliated morphologies for the MMT, with higher d-001 interplanar distance increments for the blends with higher content of polar functional groups. Mechanical properties and oxygen permeability of composites exhibited a higher improvement by the addition of MMT for higher intermolecular interactions in the composites. The results show that the exfoliated morphology can be obtained by maximizing the magnitude and number of interactions between MMT and polymer with the use of polar character copolymers. The higher the amount of interactions, given by the VA or OH polar functional groups, implies a more exfoliated morphology of the nanocomposites and in consequence a higher improvement on the mechanical and barrier properties of the composite material.