This work demonstrates upcycling mixed plastic waste (polyester, polyamide, polyurethane) into reprocessable vitrimers. Partial, controlled depolymerization of poly(ethylene terephthalate) (PET), using glycerol as a cleaving agent, yields branched PET oligomers. These oligomers, despite a wide molecular weight distribution, are used to produce a crosslinked, yet reprocessable vitrimer (vRPET) via solventless melt processing. Rheology and dynamic mechanical analysis confirm crosslinking and dynamic interactions, while tensile studies show minimal strength loss over multiple processing cycles. The method is applicable to mixed plastic waste, creating strong, reprocessable composites suitable for cyclical use.

Kok Wei Joseph Ng, Jacob Song Kiat Lim, Nupur Gupta, Bing Xue Dong, Chun-Po Hu, Jingdan Hu, Xiao Matthew Hu