Novel Bio‐Based Polyurethane Elastomers Customizable for Orthopedic Devices: Toughness, Rapid Degradability, and Safety

ABSTRACT Given the increasing global demand for sustainable materials and growing concerns over the depletion of petrochemical resources, we report the synthesis of an amorphous bio‐derived polyester diol, and this diol was polymerized with various isocyanates and butanediol, yielding a novel series of bio‐based polyurethane elastomers (BPUEs). Notably, the prepared HDI‐17% exhibited remarkable mechanical properties comparable to petroleum‐based elastomers while demonstrating exceptional biodegradability. Specifically, the elastomer indicated an enzymatic degradation ratio of 82.0% within 20 days and a relative compost degradation ratio of up to 95.5% compared with lignin over 90 days. These results significantly surpass the degradation rates of other degradable PUs reported in the literature. Regarding the degradation mechanism, our findings indicated that enzymatic degradation primarily targeted the ester groups of soft segments, with the process occurring layer‐by‐layer from exterior to interior. Additionally, microphase separation significantly influenced the degradation rate. Notably, both the BPUEs and their degradation byproduct solution were found to be nonbiotoxicity, highlighting their potential for safe application within biological systems. Furthermore, the BPUEs exhibited remarkable 3D printability, allowing for the precise fabrication of complex devices. These results mark a significant step forward in sustainable materials, providing viable options for the applications of customizing degradable biomedical devices.