Semiaromatic Polyesters Derived from Renewable Terpene Oxides with High Glass Transitions

The formation of bio-derived materials is gaining momentum in academic and industrial laboratories, though the use of terpene oxides as renewable monomers for the preparation of bio-based polymers yet remains limited. In order to advance the impact of such monomers, we have investigated the use of terpene-derived epoxides (limonene oxide, carene oxide, limonene dioxide, and menthene oxide) for the ring-opening copolymerization (ROCOP) in the presence of various aromatic anhydrides. These copolymerization reactions were mostly performed under mild reaction conditions (65 °C; low loading of catalyst: 0.50 mol %) using a binary catalyst composed of a Fe(III)-based aminotriphenolate complex and PPNCl (bis(triphenylphosphine)iminium chloride) providing partially bio-based semiaromatic polyesters with molecular weights of up to 25 kg/mol (Đ = 1.54) and glass transitions spanning a wide range from 59 to 243 °C. The copolymerization reactions proceed with excellent selectivity toward fully alternating polyesters (≥98% ester bonds) with modular thermal properties that depend on the nature of the terpene oxide used and are potentially useful toward the development of new coating and thermoset materials.