Sustainable and Degradable Thermoplastic Polyurethane Library Derived from Bio-Based Secondary Diols via Single-Feeding Strategy

Abstract Traditional polyurethanes (PUs) rely heavily on petroleum-based feedstocks and are often prepared by a two-step process. Here, bio-based dimethyl tartrate (DMT) and isosorbide (IS) were used as chain extenders to synthesize biomass-based thermoplastic polyurethane (TPU) library with poly(tetramethylene ether) glycol (PTMG) and diisocyanates through a single-feeding strategy. The obtained TPUs with tunable properties showed high number-average molecular weights of up to 43400 g/mol. DMT-based TPUs exhibited a single glass transition at −26 to 38 °C, while IS-based TPUs showed two glass-transition regions at −68 to 48 °C and 73 to 98 °C. Their initial decomposition temperatures reached 261 °C. The mechanical properties ranged from flexible elastomers to rigid plastics. DMT-based TPUs achieved elongation at break up to 2325%, whereas IS-based TPUs showed tensile strength up to 32.4 MPa. In addition, the DMT-based TPUs were degradable under alkaline conditions. These bio-based TPUs offer a promising route toward sustainable PU materials.