Advanced elasticity and biodegradability of bio-based copolyester elastomer achieved by the crystallization inhibition of isosorbide and flexibility of 1,6-hexanediol

The stability to against hydrolysis while maintaining excellent elasticity is one of the most challenging problems in the development of biodegradable and environmental-friendly polyester elastomer. While monomers of longer chain can provide higher stability, the high crystallinity and rigidity impair their application in fabricating elastomer. This work reported a star-crosslinked poly(butanediol-hexanediol-isosorbitol-itaconate-sebacate) elastomer synthesized by esterification and thermal curing. With the crystallization inhibition effect of isosorbide as a large and rigid monomer, and the flexibility of 1,6-hexanediol, the rigid (butanediol-itaconate-sebacate) copolyester system is successfully transformed from plastic to be elastomer with lower T_m and T_g, much higher elongation at break, and smaller tensile modulus, and the biodegradability is also improved. The strategy is demonstrated to be efficient and may serve as a potential technique in the future development of biodegradable elastomers.