The optimisation of food packaging films requires the films to be designed with excellent barrier properties to gases (usually water vapour and oxygen) and high mechanical and optical performances, without significant cost increase. Polymer nanocomposites may offer an interesting opportunity in this respect. This solution is studied in the present paper for both polyamide-6 (PA6) single-layer films and polyethylene/maleic anhydride grafted polyethylene/polyamide-6 (PE/PEgMAH/PA6) multilayer films. The addition of 2 wt.% of nanoclay in PA6 simultaneously improves the mechanical properties (tensile modulus, yield stress and strength), optical performances (gloss, haze and clarity) and oxygen impermeability. The processing conditions have no major influence on the studied properties, except for the optical properties. The cost increase induced by this solution is balanced by the benefits obtained in terms of overall improvement of film properties.
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