Modern Trends in Recycling Waste Thermoplastics and Their Prospective Applications: A Review

Abstract

Thermoplastics and thermosetting plastics are two major classes of polymers in that have recently become materials that are indispensable for humankind. Regarding the three basic needs of human beings—food, shelter, and clothing—polymers and polymer-based materials have gained pre-eminence. Polymers are used in food production, beginning with farming applications, and in the health sector for the development of various biomaterials, as well as in shelter and clothing for a variety of applications. Polymers are the material of choice for all modern-day applications (transportation, sporting, military/defence, electronics, packaging, and many more). Their widespread applications have created many negative challenges, mainly in the area of environmental pollution. While thermoplastics can be easily reprocessed to obtain new products, thermosetting plastics cannot; thus, this review focuses more on the use of waste from thermoplastics with less emphasis on thermosetting plastics. Hence, the review presents a concise summary of the availability of waste thermoplastics as raw materials for product development and the anticipated benefits. The prospects for waste thermoplastics and thermosetting plastics, the possibility of cleaning the environment, and the uncovering of opportunities for further research and development are presented. The limitations of the current methods of waste polymer recycling are highlighted with possible future prospects from newly introduced methods. With zero tolerance for polymer waste in our environments, potential uses for recycled thermosetting plastics are described. Waste polymers should be seen as potential raw materials for research and development as well as major materials for new products. Recycled polymers are expected to be processed for use in advanced materials applications in the future due to their availability. This review shows that the major source of environmental pollution from polymers is the packaging, hence the need to modify products for these applications by ensuring that most of them are biodegradable.

Innovative and Cost-effective Upcycling of Thermoset Plastic Waste for Sustainable Household Furniture Production

“…The contemporary world also faces the formidable challenge of recycling thermoset plastics. Unlike thermoplastics, thermoset plastics cannot be easily reprocessed or recycled due to their inherent properties [2]. The chemical nature of the thermoset matrix comprises a three-dimensional crosslink that impedes the process of re-melting by heat or solvent [3].…”

Influence of Plastic Waste Management on the Environment: A review

“…Plastics have excellent properties such as light weight, low thermal and electrical conductivity, cheap and excellent durable (Thompson et al, 2009;Rodriguez, 2023;Kibria et al, 2023) which makes them suitable for use in every sector of life such as agriculture, building, food industry, packaging industry, medicine, automobiles, building construction, communication electronics (Thompson et al, 2009;European Commission, 2021;Moranda & Paladino, 2023). In recent times, plastics have been uses as good substitutes for other materials such as wood, metals, light ceramics, and glass for the production of many products (Schyns & Shaver, 2020;Oladele et al, 2023). A major challenge is that about 40% of plastic product is short lived of less than one (1) month (Hahladakis et al, 2018; Organization for Economic Co-operation and Development, (OECD), 2022; Kabeyi & Olanrewaju, 2023) especially the packaging industry which plastics are mostly used just once and thrown away.…”

“…As at the 2020s, over 400 million metric tons of plastics are produced annually (Schyns & Shaver, 2022; United Nations Environmental Programme, (UNEP), 2023), and this is estimated to increase to 1,100 metric tonnes by 2050 (Geneva Environment Network, 2023;UNEP, 2023). In 2021, the estimated worth of plastic produced was $593 billion and this is estimated to increase to $750.1 billion by 2028 with an increase rate of 3.4% between 2021 and 2028 (Oladele et al, 2023). The demand for plastic is also increasing and is projected to increase by 37% within the next decades which amounts to about 100 million metric tonnes of plastics.…”

“…Examples of thermosetting plastics are acrylonitrile butadiene styrene, polyurethanes, and phenolic resins. They have great corrosion resistance, high mechanical strength, and thermal stability (Kibria et al, 2023;Oladele et al, 2023). These properties make them applicable in the electronic industry and automobile industries, while thermoplastics are branched, or liner structured and get soft when heated.…”

“…These properties make them applicable in the electronic industry and automobile industries, while thermoplastics are branched, or liner structured and get soft when heated. Examples are polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), high-density polyethylene terephthalate (HDPET), low-density polyethylene terephthalate (LDPET), polyvinyl chloride (PVC), and polystyrene (PS) (Alabi et al, 2019;Kibria et al, 2023;Oladele et al, 2023). These polymers are the most commercially produced polymers globally with polypropylene (PP) having 68 mt, polyethylene (PE) 166mt, polyethylene terephthalate (PET) 33mt, polyurethanes (PU) 27mt, and polystyrenes (PS) 25mt (Zheng et al, 2023).…”