Toward the recyclability of thermosetting polymers

Polymers, commonly known with the generic term “plastics,” are nowadays key materials in many industrial sectors and in our daily life. The word “polymer” is derived from the Greek words “polis” (many) and “meros” (part). Therefore, polymers are materials which consist of large molecules whose structure is made up of several smaller repeating units called monomers. They are used in a great number of applications and fields such as packaging, textile, automotive, building, aerospace or pharmacy. The broad applicability of these materials is due to their low cost and high performances, which arise from the combination of several properties, among others: easy processing, versatility, durability and high strength to weight ratio. The production of plastics has continuously increased over the last 60 years from the 1.7 million metric tons (Mt) produced in 1950 to 348 Mt in 2017 [1]. However, the mismatch between the increasing production rate and an adequate result in waste management has led to serious environmental problems [2, 3]. For this reason, in 2018, the European Commission communicated the “European Strategy for Plastics in a Circular Economy,” emphasizing the need for improved design and production of plastics to facilitate reuse, repair and recycling [4, 5]. From the data provided by Geyer et al. [6], approximately 6,000 Mt of plastic waste has been produced since 1950, and around 5,000 Mt of them has been discarded in landfills or in the natural environment, as it is shown in the following graphPeer ReviewedObjectius de Desenvolupament Sostenible::13 - Acció per al ClimaPostprint (published version