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Surface properties are extremely important for materials applied in the biomedical areas such as poly(vinyl alcohol)-PVA. The precise control of the surface characteristics on these materials may adjust and expand its applications. Here, we present a new strategy to tune the surface properties of poly(vinyl alcohol)/graphene oxide (PVA/GO) films by manipulation of GO particles (amount and level of oxidation) and also by in situ reduction of GO. Adopting a different approach from the methods currently proposed, the reduction process of GO was carried out by exposing the PVA/GO films to hydrazine vapor to maintain the degree of particle dispersion. Raman spectroscopy, contact angle (surface energy), X-ray diffraction, and atomic force microscopy were used to evaluate the interaction between PVA and GO particles and also to characterize graphene polymer composites properties at the surface of the films. The results indicated that there is a strong interaction between the GO particles and polar PVA groups mainly at a very specific stoichiometric ratio. Consequently, the surface properties of the PVA/GO films may be tuned by altering the concentration of the particles, their level of oxidation as well as by the exposure to hydrazine vapor. The impact of these affirmations is extremely important for improving the suitability of PVA in applications such as biomaterial, membranes, packaging, and others that need a rigorous control of surface properties. POLYM. COMPOS., 00:000-000, 2017.

The focus of the present work is to prepare low‐density polyethylene (LDPE)‐graphene (G) nanocomposite films with improved gas barrier properties by melt extrusion. A narrow range of the graphene (0.05–0.3 wt.%) as filler was used in the LDPE matrix. The rheological analysis indicating that there is no significant influence on the LDPE chains mobility with the addition of filler. The nanocomposites percent crystallinity (Xc%) increase from 25.0% to 31.6% compared to neat LDPE. The X‐ray diffractogram shows a change in width half height of the peak positioned at 26° ((002) plane) from 0.69 (graphite) to 1.24 (graphene), revealing the asymmetry of this plane. The optical microscopy images show a good dispersion of the nanoparticles in the polymer matrix. The mechanical properties of the nanocomposites in longitudinal direction demonstrate better improvement with addition of the filler as compared to the transverse direction. The contact angle measurements of nanocomposites for water and ethylene glycol do not shows a significant variation in comparison to neat LDPE. The nanocomposites show 26% enhancement in the oxygen barrier property. Thus, here we present the cost‐effective LDPE‐graphene nanocomposites with improve oxygen barrier property, which can be used in different industrial application especially in food packaging.