Novel biobased thermoplastic elastomer consisting of synthetic polyester elastomer and polylactide by in situ dynamical crosslinking method

Owing to the sustainability and environmental friendliness of biobased polymers, we adopted synthesized biobased polyester elastomer (BPE) and polylactide (PLA) as the two components to produce a new biobased thermoplastic vulcanizate (TPV) by an in situ dynamical crosslinking and mixing method. The effect of blending ratio on the dynamic crosslinking and micromorphology of TPV was investigated by mixing torque measurements, degree of crosslinking measurements, TEM, DSC, and rheological properties. A large amount of crosslinked BPE particles were dispersed in the PLA continuous phase, with the particle sizes ranging from 1 to 4 μm, indicating the occurrence of phase inversion during the dynamical crosslinking and mixing process. The tensile strength and elongation at break of the biobased TPVs ranged from 11.4 MPa to 17.8 MPa and 154% to 184%, respectively. Reprocessing did not significantly reduce the mechanical properties, as an indication that biobased TPVs, like thermoplastics, have good reprocessability. In vitro cytotoxicity tests showed that our TPVs were nontoxic, at least towards mouse fibroblasts. Thus, these novel biobased TPVs with excellent mechanical properties and low cytotoxicity are reported for the first time in the flied of thermoplastic elastomers for engineering and biomedical applications.