Isolation of nanocellulose from lignocellulosic biomass: Synthesis, characterization, modification, and potential applications

Lignocellulosic biomass is abundantly available in nature and is contemplated as the largest renewable resource on earth. Cellulose is a preliminary portion of the tough cell wall that surrounds the plant cells and it provides immense strength to plant stem, leaves & branches. Cellulose is considered to be a bio-polymer that can be extracted from different agricultural waste like cotton linter, bagasse, rice husk, wheat straw, jute, etc. Reduced size of cellulose fibrils, generally known as nanocellulose (NC) which is having widths in the nanometer scale and is bio-based polymer inherited with various unique and desirable traits gaining attention among researchers. There are different methods available for the synthesis of NC from lignocellulose. Nanocellulose is having high strength, toughness, high crystallinity, thermal stability, and stiffness, which paved the way for the plethora of applications in various sectors. Driven by high surface area and the presence of a large number of hydroxyl groups, it allows diverse surface modifications on the surface of nanocellulose which in turn leads to the design of various advanced functional materials. This review article outlined the recent progress made in the synthesis, characterization, and potential applications of nanocellulose derived from various lignocellulosic biomass feedstocks. Several surface modification routes such as esterification, amidation, silylation, etherification, and carbamation are also discussed which can be used to design nanocellulose based advanced materials for various advanced applications.