Magnetothermal‐Triggered Response and Self‐Healing of Recyclable and Reprocessable Nanocomposites for Actuation Systems

ABSTRACT This study investigates the incorporation of magnetic nanoparticles (MNPs) into a dynamic sorbitol‐based vitrimer matrix to develop a recyclable, innovative material for robotic applications that can be both actuated and self‐healed by the magnetothermal effects of the MNPs. This magnetic heating behavior under an external alternating magnetic field (AMF) is governed by Néel or Brownian relaxation processes of the integrated MNPs, predominantly influenced by particle size, shape, and the medium's viscosity. Hereby, the optimal particle size for high heating efficiency was determined through a size‐selective synthesis using an additive‐assisted hydrothermal method. Besides its function of enhancing the compatibility of the particles within the matrix due to decreased particle‐particle interactions, the sorbitol‐based additive also serves as a monomer for vitrimer synthesis. The vitrimer material is produced by combining the acetoacetylated monomer with Jeffamine T403 as the amine source. Notably, the nanocomposite exhibits rapid shape memory behavior when AMF is applied, with temperatures reaching up to 112°C, three times faster than simply heating it to room temperature. This approach offers promising pathways for advanced technical systems operated via internal temperature stimuli, thereby minimizing external intervention and maximizing operational reliability in variable thermal environments (e.g., at temperatures below the glass transition).