Biobased high-performance polyesters: Synthesis and thermal properties of poly(isoidide furanoate) and co-polyesters

Abstract

A fully biobased high-performance polyester was prepared by the sequential melt polymerization and solid-state post-condensation of the symmetrical 1,4:3,6-dianhydrohexitol isoidide and dimethyl 2,5-furandicarboxylate (FDME). The thermal properties of the resulting poly(isoidide furanoate) were well within the “high-performance” range with a glass transition- and melting temperature of approx. 165 and 280 °C, respectively. Since such a high melting temperature does not allow for conventional melt processing without thermal degradation of the polymer, various C2-C4 diol comonomers were incorporated in an attempt to create semi-crystalline co-polyesters with a high-glass-transition-temperature and sufficiently low melting point. It was found that semi-crystalline co-polyesters could be obtained with either low (3–5 mol%) or high (80–95 mol%) isoidide contents. All semi-crystalline co-polyesters with low diol comonomer contents (≤20 mol%) had still glass transition temperatures ≥ 118 °C despite having low molecular weights. Co-polyesters with a high diol comonomer content had lower melting points than the PiIF homopolymer, as well as a significantly lower glass transition temperature. The molecular weight of the PiIF homopolymer and a semicrystalline poly(ethylene-co-isoidide furanoate) co-polyester could be significantly enhanced by solid-state post-condensation. Thus, poly(isoidide furanoates) are an interesting class of new fully biobased polyesters that has potential in high-performance applications.