Abstract

Poly(ethylene terephthalate) (PET) is one of the most consumed plastics in the world, so it is very common to find it in the sea or ocean. Thermomechanical recycling is normally used for urban and industrial PET waste, but it is not suitable for highly degraded marine litter. Chemical recycling of marine PET litter is presented as an alternative for the valorization of this highly degraded waste. The bis(2-hydroxyethyl) terephthalate (BHET) monomer obtained can be used in the synthesis of new polymers. This study explores the potential of using BHET for the synthesis of high modulus and high strength thermoset polyurethanes. In addition, a renewable reagent, such as a polyol derived from castor oil, has been used to synthesize a recycled and biobased polyurethane thermoset (BHET-BioPU). The resulting BHET-BioPU has been thermally, thermo-mechanically and mechanically characterized to evaluate its potential applications. In addition, the recyclability by glycolysis of the BHET-BioPU has been demonstrated, thus advancing towards a circular economy. The results of this study provide fundamental knowledge for the development of sustainable, environmentally friendly and high performance materials and recyclable as well, materials, and represent an important achievement in the global effort to reduce dependence of fossil resources and plastic pollution.