Nanocellulose/Starch Biopolymer Nanocomposites: Processing, Manufacturing, and Applications

Abstract Currently, the harmful gas emission, rapid climate change, air and water pollution, and deterioration of earth's land surface are mainly produced by the aggressive utilization of petroleum-based plastic and the unmanaged garbage disposal including dumping and burning of polymeric products and substances. Many experts from throughout the globe revealed that the dumping of petroleum-based plastic and undecomposed materials is the main principle problem of environmental pollution. Hence, in order to overcome these challenging issues, biopolymers, such as starch, cellulosic-based polymer, and other biodegradable materials, are considered the most promising materials and as alternatives to non-biodegradable petroleum-based materials. This is due to their long shelf life properties such as resistance to enzymatic or chemical reaction and as they are biodegradable in nature. Starch is an abundantly available, highly biodegradable, cheap, and renewable biopolymer. However, some studies have found that the properties of starch biopolymer such as mechanical and water barrier are comparatively low than petroleum-based plastic. Therefore, nanofillers such as nanocellulose are introduced in order to overcome this issue. Nanocellulose has attracted huge attention due to its good physical and mechanical behaviors. In recent years, nanocellulose has also attracted the interest among researchers, since the technology capable to cater the environmental issues. This chapter explains the outline of current development in this particular field, including the isolation, characterization, behaviors, and various applications of nanocellulose reinforced starch biopolymer nanocomposites. Followed by explaining the distinctive properties of nanocellulose and its numerous preparation methods, an arranged introduction of various sources of nanocellulose reinforced biodegradable starch polymers is provided. Herein, nanocellulose reinforced starch biopolymer for engineering and interdisciplinary applications, comprising approaches for the transformation of various sources of cellulose to nanocellulose, and the technique of fabrication for their composites have been studied. Furthermore, the results of nanocellulose on the behavior of starch biopolymers are presented. Finally, the chapter summarizes with a new finding and innovation researches on nanocellulose reinforced starch biopolymer composites. In certain circumstances, an evaluation study was conducted between cellulose nanofiber and cellulose nanocrystals reinforced starch biodegradable polymers. Considering the vast amount of research on nanocellulose reinforced starch biopolymer composites, special highlights on such composites are allowed at the end of the review.