Poly(butylene 2,5-furandicarboxylate-co-butylene isophthalate): High-Performance Solutions for Sustainable Food Packaging

Sustainable solutions are crucial in mitigating the environmental impact arising from the mass consumption of plastic packaging, including resources depletion. Biobased plastics offer a promising path in this direction1. Polybutylene 2,5-furandicarboxylate (PBF) is currently accepted as one of the milestones of biobased plastics for food packaging2,3. While PBF demonstrates exceptional performances under several points of view4, the mechanisms underlying its peculiar properties remain the subject of extensive study. Isophthalic acid (IPA) is a diacid having a geometry that closely resembles that of 2,5-furandicarboxylic acid (FDCA) that differs from FDCA in terms of atomic composition and charge distribution. Random copolymers of FDCA and IP with butanediol (BD) in a full range of compositions were synthesized via a two-step melt polycondensation process. By characterizing the polymers and assessing the evolution of properties across the copolymeric series, we aim to evaluate the interactions contributing to the distinctive properties of both the copolymeric series and the PBF homopolymer. The molecular structure of the synthesized polymers was investigated by means of 1H and 13C NMR spectroscopy, alongside with GPC. The impact of various sample treatments, namely compression molding, cold crystallization, solvent evaporation, and dissolution/reprecipitation, on the thermal properties of the copolymers was investigated using DSC. Our findings revealed the copolymers' ability to crystallize across the entire compositional range upon proper treatment. Further validation through WAXS provided valuable information regarding potential isodimorphism. Finally, mechanical and gas barrier properties were evaluated to delineate the suitability of these copolymers for food packaging applications. References [1] L. Donkor, G. Konoth, A. Yaga, J.K. Bediako, V. Apalangya, Appl Food Res, 2023, 3, 100356. [2] G. Z. Papageorgiou, V. Tsanaktsis, D. G. Papageorgiou, S. Exarhopoulos, M. Papageorgiou, D. N. Bikiaris, Polymer, 2014, 55, 3846-3858 [3] N. Poulopoulou, G. N. Nikolaidis, R. O. Ioannidis, V. L. Efstathiadou, Z.Terzopoulou, D. G. Papageorgiou, M. Kapnisti, G. Z. Papageorgiou, Ind Eng Chem Res, 2022, 61, 13461–13473 [4] G. Guidotti, M. Soccio, M. C. García-Gutiérrez, T. Ezquerra, V. Siracusa, Gutiérrez- E. Fernández, A. Munari, N. Lotti, ACS Sustain Chem Eng, 2020, 8, 9558–9568