A facile method to synthesize bio-based and biodegradable copolymers from furandicarboxylic acid and isosorbide with high molecular weights and excellent thermal and mechanical properties

Abstract

Bio-based copolymers with high glass transition temperature (T_g) and good mechanical properties and biodegradability are highly desired for practical applications such as food packaging or in heat-resistant containers. In this work, a series of fully bio-based high-molecular-weight copolymers (PICBF(S)) were successfully prepared from dimethyl 2,5-furandicarboxylate (DMFD), isosorbide (Is), 1,4-butanediol (BDO) and dimethyl succinate (DMS) by a two-step melt polymerization, a facile and green process for practical semi-continuous production. These copolymers showed tunable T_g values varying from 43 to 122 °C and high weight-average molecular weights (M_w) ranging from 87 000 to 42 000 g mol⁻¹. A systematic study of the structure–property relationship revealed that the properties of these copolymers could be easily controlled by simply changing the composition ratio of monomers. In particular, the copolymer PI₈₀CBF₁₀S₁₀ showed a T_g value of 97.6 °C, tensile strength of 69 MPa and tensile modulus of 1330 MPa. Additionally, it showed reduced CO₂ (34 times) permeability when compared to that of poly(butylene succinate) (PBS). Also, its degradation weight loss could reach 12.7% after 28 days when incubated with lipases, which was unusual when considering its high T_g. With good gas barrier property and biodegradability, excellent thermostability and high mechanical performance, these sustainable copolymers seem to have broad potential applications in the plastic industries.