Chapter 9. Dynamic Mechanical Analysis (DMA) Study of Cellulose Nanoparticle-based Advanced Materials

The required dynamic mechanical properties and/or viscoelastic behaviour of viable cellulose matrix can be considerably improved by using green nanofillers (GNFs), which have a high aspect ratio and high active surface area. Cellulose naturally exists as a linear biopolymer in the plant cells of wood and cotton. The growing interest in the study of cellulose-reinforced renewable green reinforcing nanofillers is due to their biodegradability, low density, high aspect ratio and excellent mechanical and viscoelastic properties. These optimal properties require a good nanoparticle dispersion in the polymeric matrix, and the extent of dispersion can be analysed by dynamic mechanical analysis (DMA). DMA is a characterization technique that gives insight into the bulk properties and thermal transitions of the material analysed. The chemical compatibility between green nanofiller and cellulose plays a key role in both the dispersion of nanoparticles in the matrix and the adhesion between these phases. By chemical or mechanical modification, cellulose nanofillers can be converted into cellulose nanofibres (CNFs), cellulose nanocrystals (CNCs) and bacterial nanocellulose (BNC), all of which possess outstanding dynamic mechanical properties compared with their individual constituents. This chapter comprehensively emphasizes the processing methods of sustainable polymer nanocomposites containing GNFs for potential industrial applications, in fields such as packaging, paper and paperboard, food industry, medical and hygiene products, paints, cosmetics and optical sensors. Various extraction methods and characterization techniques, including surface modification, compatibility and dispersion methods, are discussed in detail, coupled with their effects on the overall properties.