Synthesis and characterization of novel bio-based polyesters and poly(ester amide)s based on isosorbide and symmetrical cyclic anhydrides

Three bio-based isosorbide bis(acid ester)s were synthesized by condensation of isosorbide with three symmetrical cyclic anhydrides (namely, succinic, diglycolic and phthalic anhydrides). The isosorbide-based diacids were obtained in high yields (79–97%) and converted to their diacid dichloride derivatives, which were then utilized to design series of bio-based polyester and poly(ester amide)s with wide range of thermal properties. The polyesters were synthesized in o -dichlorobenzene, utilizing either cis/trans -1,4-cyclohexanediol or 1,6-hexanediol, the polyesters were obtained in high yields (78–91%), showed good thermal stabilities, excellent solubility in organic solvents and glass transition temperatures in the range of -13.7 to 102.8 °C. Additionally, a series of novel aliphatic poly(ester amide)s was synthesized interfacially by polyamidation of the isosorbide bis(diglycolic acid) or isosorbide bis(succinic acid) derivatives with either trans -1,4-diaminocyclohexane or 1,6-hexanediamine. The aliphatic poly(ester amide)s obtained showed good thermal stabilities, good solubility in organic solvents and glass transition temperatures up to 129 °C.