Influence of Dilinoleic Succinate Segments on the Biodegradation of Poly(butylene succinate-co-dilinoleic succinate)...

Growing environmental and human health concerns associated with the persistence of nondegradable polymeric materials have intensified the global demand for sustainable alternatives. Consequently, research has increasingly focused on the development of biobased and biodegradable polymers as a means to mitigate plastic pollution. In this context, the present study investigates the biodegradation behavior of poly-(butylene succinate) (PBS) and poly-(butylene succinate-co-dilinoleic succinate) (PBS-DLS) copolymers under mesophilic anaerobic digestion (AD) and thermophilic aerobic composting conditions. After 99 days of anaerobic incubation, the tested materials exhibited negligible mineralization and no significant mass loss, indicating limited biodegradability under oxygen-deficient conditions. In contrast, all materials underwent substantial degradation during thermophilic composting (97 days), with PBS-DLS 70-30 demonstrating the highest extent of mineralizationnearly twice that of PBSand approximately 30% greater mass loss. Gel permeation chromatography (GPC) analysis revealed a decrease in molecular weight for all samples, with the most pronounced reductions observed under composting conditions. Fourier transform infrared (FTIR) spectroscopy confirmed distinct structural alterations in both PBS and PBS-DLS following exposure to both environments, particularly for PBS-DLS 70-30. Differential scanning calorimetry (DSC) analysis indicated measurable shifts in phase transition temperatures, consistent with polymer chain scission and morphological reorganization induced by degradation. Surface morphology analysis using scanning electron microscopy (SEM), optical microscopy (OM), and macroscopic imaging showed minimal surface alteration after AD, while pronounced erosion and fragmentation were evident following composting. Collectively, these results underscore the limited anaerobic degradability of PBS and the markedly enhanced compostability of PBS-DLS copolymers with increasing DLS segment content. The findings highlight the potential of PBS-DLS copolymers as promising candidates for environmentally benign materials in sustainable packaging and biomedical applications.