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Purpose – The purpose of this research is to synthesize modified thermoplastic sago starch (TPS) through in-situ mechanism by reacting sago starch with diphenylmethanediisocyanate (MDI) and castor oil simultaneously, resulting in a more homogenous and finer-sized polyurethane prepolymer (PUP).

Design/Methodology/Approach – The methods used were Thermal Gravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) for thermal characterization and stability of PUP, modified TPS non-extracted and extracted with toluene and water.

Findings – TGA test results presented shows that PUP begins to decompose thermally at a temperature of 300–500 °C. Weight loss occurs rapidly between these temperatures and is completely discharged at a temperature of 500°C, which is called weight loss transition.

Research Limitations/Implications – When extracted with toluene and a water solvent, the melting point and latent heat of fusion slightly decreased; however, it is still higher than the original value of sago. In terms of thermal stability, modified TPS decomposes and loses weight at 150–200 °C in small quantities, continues with weight loss rapidly, and is completely discharged at 500°C. The thermal stability is considered high; thus, modified TPS application can be varied.

Practical Implications – DSC analysis and TGA shows that modified TPS has good thermal characteristics and thermal stability. Modified TPS has a melting point of 104.69°C, and the latent heat of fusion (ΔH) is 234.27 J/g. This value is close to the PUP melting point and latent heat of fusion, which reveals the formation of cross-link between the starch and PUP.

Every year, tens of millions of the 1.4 billion cars on the world’s roads are decommissioned. While the ferrous and other metals that constitute about 75% of a vehicle by weight can be readily and profitably recycled, the remaining mix of plastics, glass, composites, complex materials, fragments and contaminants are mainly destined for landfill as automotive shredder residue (ASR). For every car, approximately 100–200 kg of ASR is disposed of in landfill, posing a growing technical and environmental challenge worldwide. The recovery of the ASR for high-end application is the focus of this study, aiming to optimise the use of these valuable resources and minimise the extractive pressure for raw materials, a future green manufacturing, contributing towards a zero waste circular economy. As the dissolution of carbon into iron is a key step in the manufacture of iron-carbon alloys, the feasibility of utilizing the waste polymers within ASR as sources of carbon in different areas of pyrometallurgical processing was investigated. Polypropylene and rubber, in a blend with metallurgical coke, were used as carbonaceous substrates and the slag-foaming phenomenon was investigated via the sessile drop technique in an argon environment at 1,550°C. The results indicated the rubber/coke blend achieved significantly better foaming behaviour, and the PP/coke blend exhibited a moderate improvement in slag foaming, in comparison to 100% metallurgical coke. The overall results indicated the incorporation of ASR had significant improvement in foaminess behaviour, increasing furnace efficiency.

Plastic has been a very useful material which is very cheap, easy to carry and is resilient to biodegradation. That is why plastic has been used, sometimes reused, and overused due to the reasons mentioned above. As a result, landfills and oceans are full of plastic. But if we consider all the negative health effects, environmental / ecological effects it has in present times, we can understand that it is environmentally very expensive to use plastic. Bangladesh is a relatively young country with dense population and limited resource. Proper management of plastic remains an issue with the country. Considering these, this chapter focuses on how plastic is used, how it is treated as waste and what can be possible solutions in reducing the amount of plastic in Bangladesh.

This chapter evaluates research from the past 10 years suggesting that surfing can help develop ecological sensibilities and, in turn, lead to more environmentally sustainable lifestyles and practices.

The first part of the chapter reviews some of the key themes in the movement toward more sustainable surfing, including surfers' lifestyle practices. The second part of the chapter offers more in-depth case studies of (1) the production and consumption of surfboards and (2) the emergence of wave pools. Through these two case studies the chapter explores more promising practices that are driving more desirable human–surfing–environment relationships.

The chapter highlights the key tensions in debates over the so-called sustainable surfing movement. While surfers continue to see themselves as environmentally connected and having special relationships to the environment and sustainability, there are many contradictions and inconsistencies in this relationship. The negative environmental impact of the surfing industry remains notable, including in tourism, board manufacturing, and surfing events. The chapter highlights the limitations of relying on market-based, technologically dependent approaches to sustainable development.

The chapter shows the potential and promise of technological innovation for more environmentally sustainable practices, while recognizing the ongoing challenges in changing attitudes in the surf industry, and among many participants/consumers. It echoes broader literatures showing that attitudes and behaviors around environmental issues are complex and paradoxical.