Polymers find applications in various fields ranging from protective coatings to packaging materials. The constraints due to environmental impact, recycling, weight and cost lead to the development of innovative polymeric systems with improved mechanical, thermal and barrier properties. Widely-applied in packaging applications, the coextrusion process, can again lead to a new field of composite polymer materials. Currently, the materials obtained with this process are composed of up to a dozen of polymer layers. To increase the number of layers, an innovative technique was to add layer multiplying elements for obtaining multilayer films containing hundreds to thousands of layers with layer at nanometer scale, and hence, with new properties [1]. The present study is focused on the conception and characterization of this new kind of layered structure, which is composed of LLDPE (low density Polyethylene) coupled with PA6 (Polyamide 6) and with PE-g-MA used as compatibilizer. Multilayer films of 5, 1024 and 2049 layers were so obtained. The transport properties (permeability, diffusivity, solubility) of these multi-nanolayered films (PE/PA6) were investigated by measuring water and gas (N2, O2, CO2) permeation kinetics. The improved barrier properties of these multi-nanolayered films were correlated to the structural effects induced by the forced assembly process and characterized from DSC and XRD analysis. To further improve the barrier properties, nanoclays (OMMT) were incorporated (at 0.5 and 5%wt) in the nanolayered structures. A good exfoliation and dispersion of nanofillers in PA6 layers was obtained, positively impacting the barrier performances of the PE/PA6 multi-nanolayer films. References: 1 R. Liu, A. Ranade, H. Wang, T. Bernal-Lara, A. Hiltner, E. Baer, Forced assembly of polymer nanolayers thinner than the interphase. Macromolecules 38