Castor oil-based polyurethane networks containing diselenide bonds: Self-healing, shape memory, and high flexibility

Multifunctional coating materials from bio-renewable resources have attracted significant attention in recent years. In this study, a series of multifunctional castor oil-based polyurethane (PU) networks with different hard segments containing diselenide bonds are prepared. The characteristics of PU networks such as self-healing, shape memory, mechanical behavior, and recyclable properties are investigated. All PU networks containing diselenide bonds exhibited self-healing properties under heating due to the metathesis of diselenide. PU network with a hard segment of asymmetric alicyclic structure heals entirely within 2 h under a moderate temperature (70 °C). The shape fixation and recovery ratio are kept above 99.3% and 60.6% after three cycles, respectively. Furthermore, the PU network exhibited high tensile strength (6.9 MPa), superior elongation at break up to 468%, and excellent recyclability. This work would be helpful to the development of research on functional bio-based polymer coatings containing materials dynamic covalent bonds of diselenide.