Facing the increasing challenge of plastic pollution, environmental friendly biodegradable polymer films with excellent mechanical properties have gained widespread attention. Here, inspired by natural plant components and skeletal muscle structures, we prepared a high-strength composite film with an orientation structure. Cellulose nanofiber (CNF) and sodium lignosulfonate (LS) were introduced into the poly(vinyl alcohol) (PVA) matrix, and the obtained composite film was endowed with an orientation structure by the swelling-assisted prestretching method. The physical cross-linking effect of LS effectively improved the interfacial interaction between PVA and CNF, and the strengthening effect of CNF was further enhanced by the orientation structure. Meanwhile, LS and CNF were also conducive to better thermal stability and UV-shielding performance of the composite film. Since the raw materials used are either biodegradable or extracted from biomass, this work provides inspiration for the preparation of environmental friendly polymeric materials with excellent mechanical properties.
