Performance and UV‐Induced Microplastics Formation in a PBS/PBAT Blend With and Without Joncryl Reactive Compatibilization

ABSTRACT

To the best of our knowledge, only a few studies have investigated the generation of micro‐ and nanoplastics from biodegradable polymers and polymer blends, likely due to their biodegradable nature and lower environmental persistence. Nevertheless, understanding their fragmentation behavior is crucial to clarify the effects of blend composition, processing conditions, and ageing on particle formation. In this study, poly(butylene succinate) (PBS) and poly(butylene adipate‐co‐terephthalate) (PBAT) were blended with and without the reactive compatibilizer Joncryl to evaluate the role of reactive compatibilization and the potential formation of microplastics. Spectroscopic, rheological, morphological, and mechanical characterizations were performed, together with mechanical fragmentation tests before and after ultraviolet (UV) irradiation. The results revealed significant morphological improvements in compatibilized blends, with an approximately 30% reduction in dispersed phase size. Enhanced rheological and mechanical properties were also observed, particularly in elongation at break (≈28% vs. 263%). From a sustainability perspective, no intentional microplastic release was detected. However, after 120 h of UV exposure, unintentional microplastic release occurred, with fragments smaller than 5 mm accounting for ≈16 wt% in compatibilized samples versus ≈22 wt% in uncompatibilized blends. Overall, Joncryl improved material performance while potentially reducing microplastic release.