Modification of poly(propylene 2,5-furandicarboxylate) with 2,5-thiophenedicarboxylic acid with enhanced mechanical and barrier performance

Bio-based materials provide solutions with both ecological benefits and technical feasibility for replacing traditional petroleum-based materials. This study focused on poly(propylene 2,5-furandicarboxylate) (PPF), a fully bio-based polyester with promising gas barrier properties. However, the lack of mechanical properties has become a key bottleneck in its packaging applications. Aiming at the problems of low molecular weight of PPF, Poly (propylene 2,5-thiophenedicarboxylate) (PPTh) oligomer prepared from 2,5-thiophenedicarboxylic acid and 1,3-propanediol was used to modify PPF, and high molecular weight poly(propylene 2,5-thiophenedicarboxylate-co-2,5-furandicarboxylate) (PPThF) copolyesters were prepared by melt polycondensation. The experimental results exhibited excellent CO 2 and O 2 barrier properties of up to 29.0 and 9.3 times compared with those of PET, respectively. Crucially, a brittle-ductile transition occurs without sacrificing barrier properties (elongation at break increases from 4.6% to 29%). These findings indicate that the material has the potential for packaging materials.