Synthesis and Characterization of Poly(1,4-butylene 2,5-furandicarboxylate-co-isosorbide 2,5-furandicarboxylate)

High molecular weight poly(1,4-butylene 2,5-furandicarboxylate-co-isosorbide 2,5-furandicarboxylate) copolyesters (PBSIF- x ) were synthesized via melt-polycondensation of 2,5-furandicarboxylic acid (FDCA), with varying ratios of isosorbide (ISB) and 1,4-butylene glycol (BDO) catalyzed by antimony trioxide (Sb 2 O 3 ). The PBSIF -x structures were investigated using FTIR and 1 H NMR, while the GPC analysis exhibited the copolyesters molecular weights with number average molecular mass ( M n ) in the range of 11 079–15 153 g/mol. The DSC results show that PBSIF- x copolyesters have a single glass-transition temperature ( T g ) (77.45–110.96 °C), increasing with the increase in ISB content, while TGA analysis demonstrates excellent thermal stability up to 320 °C. From the thermal result, properties of PBSIF- x copolyesters are found to be within the interval of their parent homologues poly(butylene 2,5-furandicarboxylate) (PBF) and poly(isosorbide 2,5-furandicarboxylate) (PIF), which confirms the aromatic/aliphatic blending within the polymer matrix for enhanced polymer stability and performance.