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The transport of water vapor and gases (oxygen and carbon dioxide) through poly(ethylene-co-vinyl acetate) (EVA) films of different VA content, poly(vinylchloride) (PVC) and EVA/PVC blend films, was analysed from permeation measurements.A plasticization effect of water on the material was observed for EVA films with more than 19% wt. of VA content and for the EVA/PVC blends, while for gas permeation practically all the experimental curves are characterized by a constant diffusion coefficient, whatever the VA content of the copolymer used. The increase in water absorption with the VA content leads to a steady increase in the water permeability of the EVA copolymers. By mixing the glassy PVC polymer with the EVA copolymer (in a rubbery state) reduced water and gas permeability is observed, resulting mainly from the decrease of the diffusivity due to the low segment mobility of the dense PVC material able to create hydrogen bonds between the hydrogen atoms and the Cl-substituted carbon of PVC with VA carbonyls. Compared to EVA copolymers, the EVA/PVC blends with equivalent VA contents are better in terms of selectivity.Keywords : EVA copolymers, EVA/PVC blends, water and gases permeation, DSC. * Corresponding author, stephane.marais@univ-rouen.fr 2 1-IntroductionFresh fruit and vegetables, which are living matter, sometimes need to be shipped and stored until their consumption. In order to extend their life time, it is necessary to reduce the rates of biochemical reactions which consume oxygen and produce carbon dioxide, ethylene and water [1]. There is an opposite relationship between the respiratory intensity and the storage time of the fruit and vegetables. Anaerobic fermentation of bio-components under high water and CO 2 contents often leads to bad taste and smell of fruit and vegetables. A better preservation of this type of food can thus be obtained by decreasing the respiratory intensity and the anaerobic fermentation rate via control of oxygen, carbon dioxyde and water vapor permeabilities. This can be obtained with packaging materials exhibiting high H 2 O/CO 2 and CO 2 /O 2 selectivities.To obtain a more favorable atmosphere for the preservation of some foodstuffs, micro perforation of hydrophobic films like bioriented polypropylene is currently used. The permeability of all gases is enhanced due to the additional convection flow through the created holes. As the bulk flow through holes is much faster than that through the dense polymer, but is non-selective [1], such films are only suitable for certain foodstuffs like cheese, where water vapor and CO 2 buildup must be avoided.In the present work, we investigate the use of copolymers and blends as selective packaging materials. Changes in copolymer or blend composition make it possible to vary the film permeability and selectivity properties. As ethylene-vinyl acetate (EVA) copolymers with vinyl acetate content varying from 2% to 70%. are commercially available, they are worth being studied as packaging materials.In previous papers, the transport...