Bio-based dual dynamic covalent adaptive networks based on itaconic acid with superior degradability, reprocessability, and mechanical properties

Abstract

Thermosetting polymers are increasingly integral to diverse industrial applications due to their superior mechanical robustness and dimensional stability. However, challenges associated with their recyclability and reprocessability persist, limiting their environmental sustainability. Covalent Adaptive Networks (CANs) present a promising pathway to overcoming these limitations by introducing dynamic covalent bonds, which facilitate enhanced recyclability and reprocessability of thermoset resins, Additionally, the use of bio-based feedstocks offers a promising route to mitigate the environmental impacts of polymer production. Herein, we report the development of an innovative thermosetting polyurethane synthesized from bio-derived itaconic acid and vanillin, featuring dual dynamic covalent bonds: imine linkages and disulfide linkages. These bonds endow the polyurethane network with inherent recyclability, reprocessability, degradability, and shape memory characteristics. After three thermal reshaping cycles, the material exhibited significant tensile strength recovery, exceeding 70 %, and demonstrated rapid degradability within 5 h at 50 °C. These findings represent a strategic advancement in polyurethane technology, offering a potential route to address the environmental challenges associated with traditional thermosets. The development of this multifunctional, sustainable material aligns with the growing emphasis on designing polymers that foster both resource sustainability and a reduced environmental footprint.