Effect of gamma irradiation on chemico/physical properties and enzymatic hydrolysis of poly(butylene 2,5-furanoate) based films

Poly(butylene 2,5-furanoate) (PBF), a bio-based polyester derived from 2,5-furandicarboxylic acid (FDCA), is a promising alternative to conventional polyesters, like polyethylene terephthalate (PET), due to its superior barrier properties, mechanical strength, and recyclability. These characteristics make PBF particularly suitable for specialized purposes, including medical packaging, where structural integrity and sterility, achieved via gamma irradiation, are critical. However, gamma irradiation can induce structural changes like chain scission, branching, and/or cross-linking, which can alter thermal stability, mechanical properties, and biodegradability. In this study, PBF samples were exposed to different doses of gamma rays (10-300 kGy) to investigate the impact of irradiation on structural, thermal and mechanical properties, as well as on enzymatic hydrolysis. At moderate doses (25-50 kGy), chain scission enhanced enzymatic hydrolysis. At higher doses (100-300 kGy), HPLC analysis revealed decreased release of monomers, suggesting presence of not fully hydrolysed dimers and oligomers. GPC analysis, tensile tests and contact angle measurements, indicated structural changes and possible grafting and/or cross-linking in the samples irradiated at the highest doses. TGA, DSC and FT-IR analyses further confirmed chain scission and cross-linking as dose-dependent modifications. This study demonstrates that gamma irradiation can be employed as a pre-treatment to enhance enzymatic degradability of PBF without compromising performance. Moderate irradiation doses were identified as optimal, as they accelerate PBF hydrolysis while preserving the polymers functional properties. Furthermore, such doses are used to sterilize medical devices, including biomedical packaging. These findings contribute to develop sustainable, high-performance polymers for medical and industrial application, advancing circular economy goals and environmental sustainability.