Abstract
Currently, there is a growing interest in the development of reusable polymer matrix composite materials. In this regard, it is commonly known that although thermoplastic matrices can be reprocessed, they generally have worse mechanical properties, and their processing is much more complex than that of thermoset matrices, due to the high viscosities involved during manufacturing processes [1]. Therefore, the development of new thermoset matrices that can be reused is key. In this context, solutions such as polymers based on dynamic covalent bonds emerge, which allow the material to be reprocessed by heating it above its Tg [2], as seen in previous chapters. This would allow reprocessing similar to that of thermoplastic polymers, enabling these composite materials to be used again for new applications.
Therefore, considering the development of these new materials and the existing concerns about developing more sustainable manufacturing techniques and materials, the need arises to establish new methods for the proper identification of both the composite material waste generated and those composite materials that are recycled, i.e., those that are reused. Products can be labeled to facilitate better recovery at the end of their useful life (End of Life, EOL), especially due to the wide variety of possible material compositions in composite materials. Labeling is mandatory for certain plastic products in the automotive industry (including composite materials) according to the End-of-Life Vehicle (ELV) directive [3]. There are standards for labeling products in other sectors. Some high-value products in the aerospace and automotive industries now incorporate Radio Frequency Identification (RFID) tags for tracking product life cycle management (Product Life Management, PLM) and ensuring provenance and traceability. These tags may contain data about the material to facilitate higher-value recycling and could be linked to virtual databases that include material origin, manufacturing, and usage data throughout the entire life cycle.
Proper identification of components can also be done through the Digital Product Passport proposed as part of the ESPR (Ecodesign for Sustainable Products Regulation) [4], to maintain adequate traceability of products in terms of material technical characteristics, repair information, etc., so that consumers have a complete understanding of the materials and their environmental impact, in order to establish appropriate reuse techniques. The ESPR, in turn, aims to design components that result in more reliable, durable, reusable, repairable, easy-to-maintain, recyclable, and energy-sustainable products.
In addition, waste can be classified using EWC codes (European Waste Catalogue). This can enable proper identification of waste that may be more hazardous or waste that could be reused at the end of its first life cycle.
Therefore, this chapter aims to address, in a simple manner, those methods for identifying composite materials, both focused on the traceability of products through digital passports, and for managing the waste generated during their service life using EWC codes.
0
CHAPTER 6: MANAGEMENT OF COMPOSITE MATERIALS AT THE END OF USE: CURRENT SITUATION 
