The utilization of cellulose nanocrystals (CNCs), a renewable and eco-friendly nanomaterial, has emerged as the favored option for sustainable fillers. This paper presents diverse methods for CNCs preparation, including acid hydrolysis, oxidation, mechanical method, enzymatic hydrolysis, solvent method and hybrid approach. The strategies for modifying CNCs can be summarized as encompassing physical adsorption through non-covalent bond interactions and chemical modifications via covalent bonding. Moreover, the applications of CNCs in sensing systems, electronic skin devices, packaging materials, electronics industries, stabilizers and cosmetics are discussed with a particular emphasis on their contribution to enhancing polymer matrix properties. Lastly, future prospects for the advancement of CNCs are explored with a focus on its potential impact on sustainability efforts.
