Progress in nanocellulose and its polymer based composites: A review on processing, characterization, and applications
Shagun Varshney, Nidhi Mishra, M. K. Gupta
Abstract
Abstract Contamination of the ecosystem from plastics is the most prominent concern of current times. Natural materials like plant‐based fibers from cellulose, hemp, sisal, etc., are preferred and being looked upon as better alternatives. Cellulose, being biocompatible and biodegradable, possesses appreciable properties. Its nanoscale form, called as nanocellulose, can be extracted from agricultural residue and lignocellulosic biomass through different chemo‐mechanical techniques. Chemical methods include alkaline treatment, chemical bleaching, acid hydrolysis, and TEMPO mediated oxidation, whereas high‐pressure homogenization, grinding, cryogenic crushing, and ultrasonication are the mechanical methods used for the isolation and extraction of nanocellulose. This review presents a comprehensive analysis of various processing and extraction methods used for nanocellulose. The review also brings an insight into nanocellulose‐polymer based composites including their mechanical, biological, thermal, and physical properties. A detailed discussion on nature, morphology, size, and other parameters through different characterization techniques is also presented in this review. Finally, the applications of nanocellulose in biotechnology, biomedical, mechanical, material science, chemical, and electronics engineering have also been discussed.