Bio-based vitrimer-like polyurethane based on dynamic imine bond with high-strength, reprocessability, rapid-degradability and antibacterial ability

Synthesis of vitrimer with dynamic covalent bond is a surprising solution to overcome the inherent limitations of traditional thermosets. A bio-based vitrimer-like polyurethane formed by castor oil, vanillin, m-xylylenediamine and 4,4 '-dicyclohexylmethane diisocyanate in the preparation has superior mechanical properties, good solvent resistance, good thermal stability. Furthermore, the existence of dynamic imine bond in the vitrimer-like polyurethane is prone for polyurethane to rapid stress relaxation behavior, remoldability, weldability, antibacterial ability. With the hydrolysis of the imine bond, the material can be rapidly degraded at 60 degrees C for 1 h. In addition, it's commendable that the material exhibits excellent reprocessability that can be maintained at 86% even after 3 consecutive smash/mold pressing cycles. This work provides a promising method to manufacture bio-based polyurethane thermosets with excellent reprocessability, rapidly-degradable and antibacterial property, which has also promoted the high-value utilization of biomass materials.

Automated summary

The synthesis of a bio-based vitrimer-like polyurethane with dynamic covalent bonds has shown superior mechanical properties, solvent resistance, thermal stability, rapid stress relaxation behavior, remoldability, weldability, and antibacterial ability. The material can be rapidly degraded at 60 degrees C and exhibits excellent reprocessability, maintaining 86% performance even after 3 consecutive smash/mold pressing cycles. This work provides a promising method for the high-value utilization of biomass materials by manufacturing bio-based polyurethane thermosets with excellent reprocessability, rapid degradation, and antibacterial properties.