Opportunities for Cellulose Nanomaterials in Packaging Films: A Review and Future Trends

Performance requirements for packaging films may include barrier properties, transparency, flexibility, and tensile strength. Conventional packaging materials, such as plastic films and laminates, are typically made from petroleum-based polymers. Currently, there is a drive to develop sustainable packaging materials. These alternative materials must be able to be manufactured economically and on a commercial scale, exhibit barrier properties and transparency, and provide adequate mechanical performance. As a biobased, renewable material, cellulose nanomaterials (CNs) are ideally suited to be used in sustainable packaging applications. CNs include cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs) and each can provide benefit to packaging films. Manufactured CNF films can be used as packaging films or laminates and have been shown to have good strength properties and good barrier properties, particularly at low humidity. Both CNCs and CNFs can be added to other polymers to improve strength and barrier properties. The flexibility of CNs to be used in a variety of ways in packaging applications has resulted in considerable attention and research activity. This article summarizes the current applicability for CNs in packaging films and discusses the future trends and opportunities for these materials.