Chapter 3 - Thermoplastic starch

Abstract

Increase in depletion of fossil-fuel and climatic changes have made pressure on increasing the renewable carbon content of plastic. Globally, around 8 billion tons of plastic polymers were generated, and into which 6 billion ton of plastic leftover were engendered alone in 2018, making it a serious threat. And therefore, bioplastic demand has increasingly become attractive in academic and industrial sectors both due to its biodegradable nature. Bioplastics are highly resistance to chemical and enzymatic reaction. Starch, cellulose, protein, and chitin are mainly found in nature as renewable polymers. Among them, starch has been getting much more attention because of its high productivity from renewable resources. The pure form of starch (native starch) is converted to thermoplastic starch (TPS) in the existence of surplus water and plasticizers. But the major drawback of native starch in TPS beside high moisture sensitivity is deprived mechanical properties and thermal stability. Numerous investigations were conducted to lessen or overcome from these negative sides of TPS, by chemically modifying the starch solution or by mixing them with different biodegradable polymers, polyesters, and microfibrils. Bioplastics will have more environmental value in upcoming days as they are alternative of conventional plastics and will directly base on the level of biodegradability. This leads the application of TPS-based material in various food packing, agriculture and horticulture field, without forming any toxin. In this chapter, characterization of TPS and its properties, biodegradability, and methods of preparation of TPS and its application are discussed in brief.