One-Pot Recycling Technology of Post-Consumer Plastics: Dissolution and Incremental Polymerization of Expanded Polystyrene Waste (wEPS)

The accumulation of plastic wastes has become a growing concern all over the world. In 2021, global plastic production rose 4% to more than 390 million tonnes. In according to the report by PlasticsEurope, the total amount of plastic waste generated in the EU was estimated at 57.2 Mt. Packaging is one of the most important and frequent applications of plastic materials and is also a key environmental concern. In 2020, 35% of post-consumer plastics waste was sent to recycling, 42% is sent to combustion for energy recovery and 23% is sent to landfill. The recycling of plastics represents the appealing and challenging solution needed to create a circular economy for plastics. Expanded polystyrene (EPS) is commonly used in the packaging sector, mainly because of its excellent impact strength, acoustic and thermal insulation, lightness, and easy processing. However, the high volume-to-mass, making EPS suitable for these applications, represents the real challenge for the assessment of its best end‐of‐life (EoL) management. Chemical recycling methods of waste expanded polystyrene (EPS) by a closed-loop design using a one-pot recycling technology are highly sought. In this frame, the recycling EPS by dissolution and re-polymerization in styrene, is reported. The method is advantageous because it allows to upcycle EoL EPS by its re-polymerization in the monomer solution, thereby avoiding the need for polymer-solvent separation.