Cellulose and Lignin Nanoparticles in the Development of New Sustainable Applications

Cellulose nanoparticles (CNs) have emerged as one of the most promising eco-friendly materials due to their sustainable potential and outstanding physical and mechanical properties. These properties include exceptional optical attributes, an anisotropic shape, and high mechanical strength. A significant factor that adds to their appeal is that they are derived from cellulose, a resource that is abundant, non-toxic, biodegradable, and biocompatible resource. Lignin, which once was considered an undesirable by-product of the pulping process, has been the subject of extensive research to enhance its value. Although it is primarily used to produce renewable energy in industries, the growing potential of lignin from both process and economic perspectives is noteworthy, especially as the global demand for bio-based products increases. However, the methods employed to valorize this macromolecule present challenges, leaving lignin a somewhat underexploited renewable resource. An innovative approach for lignin has been its conversion into lignin nanoparticles (LNPs). Both LNPs and CNs are emerging as valuable materials in a range of applications in materials engineering, from packaging to biomedical fields. The development of new nanocomposites, derived from CNs and LNPs, merges the benefits of these nanomaterials with their plant-based origins. When integrated with other polymeric matrices, they offer unique properties such as hydrophobicity, UV protection, and antimicrobial activity. This chapter explores the latest advancements in CNs and LNPs production and their potential uses, drawing from contemporary literature.