Synthesis of bio-based poly(ester-ether) elastomers from 2,5-furandicarboxylic acid (FDCA) with excellent thermo-mechanical properties

As a novel polyester possessing high melting temperature and well crystallization ability, poly(1,4-cyclohexanedimethylene furandicarboxylate) (PCF), produced from bio-based 2,5-furandicarboxylic acid and 1, 4-cyclohexanedimethanol, could be used as promising hard segment to develop new bio-based thermoplastic poly(ether-ester) elastomer (TPEE). Multiblock poly(ether-ester)s based on PCF, with molecular weight (Mn) of soft segments poly(tetramethylene glycol) (PTMG) ranging from 250 to 2900 g/mol while maintaining the weight fraction at 70%, were synthesized to investigate the effects of soft segments length on microphase structure and thermodynamic properties of copolymers. The results show that the increase in Mn of the soft segment promotes the microphase separation of the copolymers. Macroscopically, copolymers have excellent comprehensive properties. Tm was promoted from 126.0 to 228.7 °C, and Td,5% was higher than 320 °C. The tensile strength and modulus of resulting copolymers were within the range of 14–26 MPa and 29–53 MPa, respectively, with elongation at break exceeding 550%. The copolymer exhibited elastic recovery ratio of 75.5% at 200% strain when the Mn of PTMG unit was 2000 g/mol. This work introduces a new bio-based TPEE and enriches a detailed understanding of the impact of soft segments length on the structural properties of TPEE, which is fundamental to design tailor-made TPEE with desired properties.