Circular economy approach to recycling technologies of post-consumer textile waste in Estonia: a review

Circular Production, Designing, and Mechanical Testing of Polypropylene-Based Reinforced Composite Materials: Statistical Analysis for Potential Automotive and Nuclear Applications

The circularity of polymer waste is an emerging field of research in Europe. In the present research, the thermal, surface, mechanical, and tribological properties of polypropylene (PP)-based composite produced by injection molding were studied. The pure PP matrix was reinforced with 10, 30, and 40% wt. of pure cotton, synthetic polyester, and polyethylene terephthalate post-consumer fibers using a combination of direct extrusion and injection molding techniques. Results indicate that PP-PCPESF-10% wt. exhibits the highest value of tensile strength (29 MPa). However, the values of tensile and flexural strain were lowered with an increase in fiber content due to the presence of micro-defects. Similarly, the values of modulus of elasticity, flexural modulus, flexural strength, and impact energy were enhanced due to an increase in the amount of fiber. The PP-PCCF-40% wt. shows the highest values of flexural constant (2780 MPa) and strength (57 MPa). Additionally, the increase in fiber loadings is directly proportional to the creation of micro-defects, surface roughness, abrasive wear, coefficient of friction, and erosive wear. The lowest average absolute arithmetic surface roughness value (Ra) of PP and PP-PCCF, 10% wt., were 0.19 µm and 0.28 µm. The lowest abrasive wear value of 3.09 × 10-6 mm3/Nm was found for pure PP. The erosive wear value (35 mm3/kg) of PP-PCCF 40% wt. composite material was 2 to 17 times higher than all other composite materials. Finally, the single-step analysis of variance predicts reasonable results in terms of the p-values of each composite material for commercial applications.

Emerging Technologies Supporting the Transition to a Circular Economy in the Plastic Materials Value Chain

Plastic waste has come to the forefront of academic and political debates as a global problem that demands an urgent solution. Promoted by policymakers, academia, and corporations alike, the circular economy model presents a viable path to reach more sustainable levels of development. Emerging and disruptive technologies can catalyse the transition to a circular economy, but their application to the transition of the plastic materials realm is not fully understood. Based on a systematic review of the literature, this paper aims to understand the role of key emerging technologies in the transition towards a circular economy in the plastic materials value chain, their potential impact, as well as the barriers of adoption and diffusion. Employing the ReSOLVE framework, the analysis reveals that rather than individual technologies, four technology sets associated with Industry 4.0, distributed economies, bio-based systems, and chemical recycling stand as major enablers of this transition. The complementarity of technologies and the change needed from a systemic perspective are discussed along with a proposal for governance and practical implementation pathway to overcome barriers and resistance to the transition.

A comprehensive review on textile waste valorization techniques and their applications

An increase in population compels the textile industry to expand production to fulfill the apparel requirement, resulting in huge textile waste. These wastes are managed either by landfilling or incineration processes, which negatively contribute to the environment. Converting waste into value-added products is essential to reducing environmental pollution and thereby achieving a circular economy through proper waste management practices. This paper provides a comprehensive overview of different categories and forms of textile waste, their source of generation, the reusing capability of the textile industry, other valorization potentials in different fields, and various challenges associated with their valorization practices. This review presents textile wastes as the raw material source for preparing different value-added products such as in manufacturing textiles, packaging materials, plastics, composites, construction applications, energy generation, chemical additives, composting, and several other applications.