Unlocking the potential of furan-based poly(ester amide)s: an investigation of crystallization, molecular dynamics and degradation kinetics of novel poly(ester amide)s based on renewable poly(propylene furanoate)

Ιn this work novel polyester amides (PEAs) based on biobased poly(propylene furanoate) (PPF) were synthesized via traditional melt polycondensation, utilizing a preformed symmetric amido diol (AD) containing two internal amide bonds. Materials of random structure were obtained without intramolecular bonding usually observed in furan dicarboxylic acid (FDCA) based polyamides. Their crystallinity and crystal structure were assessed via the combination of differential scanning calorimetry (DSC), X-ray diffraction (XRD) and polarized optical microscopy (POM). Furthermore, thermal degradation of the furan-based PEAs was thoroughly investigated for the first time, employing thermogravimetric analysis (TGA) kinetic modeling and Pyrolysis-Gas Chromatography–Mass Spectroscopy (Py-GC MS). Finally, the complex molecular dynamics of PEAs was studied employing broadband dielectric spectroscopy (BDS). The presence of AD led to enhanced crystallization, both in terms of quantity and rate, as a consequence of an altered, semicrystalline morphology, proving the targeted aim was successfully achieved. This is most probably a direct effect of the presence of AD and the suppression of intramolecular hydrogen bonds, that result in enhanced chains mobility (diffusion). This study shows that PEAs from have the potential to further enlarge the properties and applications of polyesters derived from FDCA.