Aware of the European Environmental Sustainability policies, the University of Aveiro (UA), located in Portugal, applied to the Environment, Climate Change and Low Carbon Economy Program promoted by the General Secretariat for the Environment and Climate Action. This application led to the successful implementation of the REAP project (REAP stands for Recycling and Refund of PET and Aluminium Packaging). The major goal was to reimburse the UA community for each polyethylene (PET) bottle that they deposit. INFINITUM, a Norwegian company, was the selected partner to install the collecting and refunding equipment dispersed throughout the UA campus and their polytechnical schools. It is expected that dedicated collecting and separating system will result in PET waste bottles with a lower degree of contamination. Thus, PET recycling into new products will be easier and more beneficial.

Two different applications were studied for the collected PET bottles, namely 3D printing filaments incorporating recycled PET (rPET) and packaging with 100% rPET content. Before moving to the experimental studies, PET bottles were initially sorted by brand and by rPET content. The majority of the PET water bottles available in the market have already incorporated around 25 to 30% (w/w) of rPET. Post-consumer PET bottles were then granulated into flakes, after an intensive cleaning process, including paper and glue removal. Filaments with different quantities of rPET were prepared, including filaments with 100 % rPET content. The small processing window of PET, and consequently, rPET, revealed challenges in the dimensional accuracy of the prepared filaments. Mechanical, thermal, morphological, rheological and chemical analyses were conducted on the developed filaments and printed specimens. Another application studied was the incorporation of post-consumer PET flakes in the preparation of water bottles. Initially, preforms were injected and then blown into bottles (20 cl). A recycled content of up to 50% (w/w) was explored. The migration of rPET components to water was also determined.

The REAP project contributed, not only to the development of recycled PET-based material solutions but also impacted positively the social awareness of the UA community for sustainable practices.