Chapter 10. Physico-chemical Properties of Cellulose Nanoparticle-based Advanced Materials

Nanocellulose has attracted substantial interest as a promising candidate for bio-nanocomposites due to its excellent physico-chemical properties such as high surface area, high mechanical strength and low density. The application of cellulosic nanoparticles for the fabrication of bio- and nanocomposites is a relatively new field of research. Cellulose micro- and nanofibres can be used as reinforcement in biocomposite materials as they provide higher mechanical, thermal and biodegradation properties to composite. In this chapter, we consider cellulose nanocrystals (CNCs) and cellulose nanofibres (CNFs) as the nanocellulosic materials. A brief discussion on their source and properties is also incorporated. Because of the numerous publications on cellulose nanocomposites, this chapter discusses the structure of different cellulose substrates and their different types of expedient properties. A comprehensive discussion on the gas barrier, thermal, mechanical, water absorption, permeability and crystallinity which are responsible for gaining so much interest towards these materials is also included. The chapter also discusses relatively new applications of nanocellulose, namely, water sorption and gas barrier functionality. The mechanism of the oxygen barrier and the effect of nanocellulose-based materials on different gas barrier properties are also discussed. This chapter, overall, is a guide to help in designing nanocellulose-based composites through the utilization of nanocellulose-specific properties and the selection of functional polymers, paving the way to a selection of specific cellulose nanoparticles depending on their property.