Acylhydrazones as Reversible Covalent Crosslinkers for Self-Healing Polymers

The utilization of dynamic covalent and noncovalent bonds in polymeric materials offers the possibility to regenerate mechanical damage, inflicted on the material, and is therefore of great interest in the field of self-healing materials. For the design of a new class of self-healing materials, methacrylate containing copolymers with acylhydrazones as reversible covalent crosslinkers are utilized. The self-healing polymer networks are obtained by a bulk polymerization of an acylhydrazone crosslinker and commercially available methacrylates as comonomers to fine-tune the T-g of the systems. The influence of the amount of acylhydrazone crosslinker and the self-healing behavior of the polymers is studied in detail. Furthermore, the basic healing mechanism and the corresponding mechanical properties are analyzed.