High performance bio-based polyurethane elastomers: Effect of different soft and hard segments

In this work, a series of high performance bio-based polyurethanes (bio-PUs) were synthesized from polylactide (PLA)-based diols, different diisocyanates (TDI, MDI, HDI, IPDI) and chain extender 1,4-butanediol, in which different soft and hard segments are used to adjust their transition temperatures and mechanical properties. Poly(lactide- co -caprolactone) copolymer diols ( co -PLAols) instead of PLA diols as the soft segment improved the thermal stability and mechanical properties of the synthesized bio-PUs. Among them, MDI-based bio-PUs have the highest T g (43.8 °C), tensile strength (23.5 MPa) and modulus (380.8 MPa), while HDI-based bio-PUs have the lowest T g (21.4 °C) and highest elongation at break (580%). Especially, the bio-PUs synthesized from co -PLAols and MDI demonstrate better mechanical properties, closed to petroleum-based commodities. Furthermore, the obtained bio-PUs display good shape memory properties at body temperature and cytocompatibility. Therefore, these bio-PUs are promising for applications in biomedical fields.