Synthesis of Biomass-Based Monomers from Biomass-Based Furfural for Polyesters and Evaluation of Their Biomass Carbon Ratios

Commercially available furfural has been produced from hemicellulose derived from inedible-biomass-based resources, and furfural has been converted into commercially available furan by decarboxylation. These heterocyclic compounds are important chemicals for the production of biomass-based monomers. Oxidation of furfural gave a mixture of maleic acid and FA. These were hydrogenated to give succinic acid. Dimethyl succinate was synthesized from FA by esterification and hydrogenation. These chemicals are useful as biomass-based monomers for biomass-based plastics. Fully biomass-based poly(butylene succinate) (PBS) was obtained by polycondensation of biomass-based 1,4-butanediol and biomass-based succinic acid or dimethyl succinate. Succinic anhydride (SAn) and tetrahydrofuran (THF) were also synthesized from furfural. Fully biomass-based poly(butylene oxide-co-butylene succinate) was obtained by ring-opening polymerization of biomass-based SAn and THF. Partially biomass-based poly(butylene terephthalate) was obtained by polycondensation of biomass-based 1,4-butanediol and petroleum-based terephthalic acid. The biomass carbon ratio calculated from C-14 concentrations measured by accelerator mass spectroscopy verified that the PBS obtained in this study contained only biomass carbon. The polycondensation of biomass-based 1,4-butanediol and petroleum-based terephthalic acid or dimethyl terephthalate gave partially biomass-based poly(butylene terephthalate), which is an engineering plastic.