Biosourced Aromatic Derivatives in the Upcycling of Recycled PET: Mellophanic Dianhydride as a Chain Extender

Preparation and use of biosourced mellophanicdianhydrideas a chain extender for R-PET as an alternative to oil-based pyromelliticdianhydride. The synthesis of mellophanic dianhydride (MEDA) frombiosourced1,2,3,4-benzene tetracarboxylic derivatives and its use as a chainextender for mechanically recycled PET (R-PET) as an alternative totraditional oil-based pyromellitic dianhydride (PMDA) is reported.The rheological tests performed on the R-PET extruded with MEDA haveshown similar results to those obtained with PMDA, and dynamic mechanicalthermal analysis (DMTA) showed that, in the 90-110 & DEG;Crange (i.e., the temperature range commonly used for blow moldingof bottles), Young's modulus of R-PET containing MEDA is about20% higher in comparison to that of pristine R-PET. The advantageof MEDA is that it can be prepared using building blocks obtainedfrom agricultural waste via a sustainable protocol,whereas PMDA is a product of oil-based chemistry.