Poly-paper: A sustainable material for packaging, based on recycled paper and recyclable with paper

Background: Until now, environmental sustainability issues are almost entirely unsolved for packaging materials. With the final aim of finding materials with a single recycling channel, cellulose fiber/poly(vinyl)alcohol composites were investigated. Methods: After extrusion and injection molding, samples of composite with different cellulose fiber content (30%, 50% and 70% w/w) were tested. Results: Tensile mechanical tests exhibited an improvement in composite stiffness when the reinforcement content was increased together with a decrease in composite elongation. Solubility tests performed at room temperature and 45°C showed different behavior depending on the water-resistant film applied on the composite (50% cellulose fiber content). In particular, the uncoated composite showed complete solubility after 2 hours, whereas at the same time point, no solubility occurred when a non-water-soluble varnish was used. Conclusions: The proposed composites, named Poly-paper, appear to warrant further investigation as highly sustainable packaging.