Polyethylene terephthalate (PET) in the packaging industry

Polyethylene terephthalate (PET) is the third most widely diffused polymer exploited in the packaging industry, monopolizing the bottles market for beverages, and covering almost the 16% of the European plastic consumption in the packaging industry. Even if PET primarily derived from fossil sources and remains not-biodegradable in the environment, novel advancements in the field pointed out the possibility of producing PET in a more sustainable way (e.g., from biomasses) or the possibility of biodegrade this polyester through the enzymatic action of specific genetically-modified/isolated bacteria/enzymes. By considering also the high recyclability of PET, and the possibility of potentially indefinitely re-use this material, one can assume that the future of PET is still to be written. Therefore, all aspects involving the industrial production (with traditional and sustainable chemical routes), intrinsic physicochemical/thermal/mechanical properties, undesired degradation phenomena, chemical/mechanical recycling processes, and processability of PET are here critically discussed. A particular emphasis has been dedicated to the role of PET in the packaging industry. The main achievements in the PET processing for food packaging are presented, analyzing advantages and disadvantages of each technology. This document aims at providing a useful instrument that collects past, present, and future of the PET: a well-consolidated material that has been able to renew itself over time.