A novel poly (pentylene 2,5-furandicarboxylate-co-pentylene 2,6-naphthalate) polyester derived from bio-based 2,5-Furandicarboxylic acid with superior gas barrier properties

As petroleum resources are developed and utilized, the role of bio-based polymers as alternatives in the packaging field is becoming increasingly prominent. The development of bio-based derived polyesters with excellent air barrier and mechanical properties is both significant and challenging. In this study, we report the synthesis of a series of Poly(pentylene 2,5-furandicarboxylate-co-pentylene 2,6-naphthalate) (PPeNFs) using dimethyl-2,6-naphthalenedicarboxylate (2,6-DMNDCA) as a comonomer. The introduction of 2,6-DMNDCA not only enhanced the thermal and mechanical properties but also improved UV and gas barrier performance. At 50 % 2,6-DMNDCA content, the copolyester exhibited an excellent elongation at break (ε_b = 377.1 %) and tensile strength (σ_b = 40.6 MPa). A strawberry preservation experiment demonstrated that the modified copolyester outperformed traditional commercial plastic products. This work offers a new pathway for the application of polyesters in flexible packaging materials and provides valuable insights for future development in the field.