Poly(butylene oxalate-co-terephthalate): A PBAT-like but rapid hydrolytic degradation plastic

Concerns over worldwide plastic pollution have led to the development of biodegradable polyester materials with excellent physical and chemical properties through the copolymerization of poly(butylene oxalate) (PBOx). As a result, poly(butylene oxalate-co-terephthalate)s (PBOTs) with varying compositions, were prepared by incorporating aromatic units. Studies have indicated that PBOT-47 (with a 47% molar terephthalate), exhibits exceptional mechanical properties. With an elongation at break of 1160% and a tensile strength that remains above 30MPa, similar to or even better than those of the commercial biodegradable plastic poly(butylene adipate-co-terephthalate) PBAT-47 (47% molar terephthalate). Moreover, the permeability coefficients of PBAT-47 for H2O, CO2 and O2 were 5.8, 50.6 and 5.6 times higher than that of PBOT-47, revealing the superior barrier properties of PBOT. Through experimental research and theoretical simulation, the mechanism of the copolymer hydrolysis was elucidated. The readily hydrolytic nature of the oxalate unit endows it with the capacity for rapid degradation, possessing the potential to be a short-term degradable material with physical properties similar to PBAT. ENVIRONMENTAL IMPLICATION The plastic pollution crisis is becoming increasingly worse, causing habitat alteration, climate change, and a loss of biodiversity. Biodegradable polyesters are recognized as a potential solution to this problem, but they face difficulty in quickly breaking down molecular chains into monomers or oligomers without enzymes catalysis. Attempts to introduce terephthalate units (BT) into the PBOx framework to synthesize PBAT-like poly(butylene oxalate-co-terephthalate) (PBOT) will endow the co-polyester with tunable degradation and mechanical properties. The outstanding non-enzymatic degradation advantage of PBOT will compensate for the shortcomings of PBAT-like materials that cannot be degraded in the short term under natural circumstances.