High-strength, water-resistant polyvinyl alcohol films reinforced with regenerated cellulose fibers for food packaging

Polyvinyl alcohol (PVA) film, a promising biodegradable packaging film material, shows low water resistance and mechanical properties, which hinder its application in the packaging field, particularly in humid or aqueous environments. Herein, PVA/regenerated cellulose fibers (RC) blend films (PVA/RC films) were fabricated by a simple controllable regeneration of cellulose fibers in an aqueous solution of PVA. The potentiation formed by the uniformly distributed RC in PVA/RC films and the competitive advantage of hydrogen bond (N···H-O) formation between urea and PVA afforded superior water resistance and mechanical characteristics to PVA/RC films. In particular, PVA/RC films displayed good tensile strength and elongation at break under dry and humid conditions (75.97 and 35.37 MPa; 281.17% and 624.83%, respectively). The shelf life of fresh strawberries packed in these blend films was extended by an additional 4 days. The present study revealed a simple and economical approach to manufacture PVA-based packaging film materials for use in humid and aqueous environments.