Harnessing Labile Bonds between Nanogel Particles to Create Self-Healing Materials

Using computational modeling, we demonstrate the self-healing behavior of novel materials composed of nanoscopic gel particles that are interconnected into a macroscopic network by both stable and labile bonds. Under mechanical stress, the labile bonds between the nanogels can break and readily re-form with reactive groups on neighboring units. This breaking and re-forming allows the units in the network to undergo a structural rearrangement that preserves the mechanical integrity of the sample. The simulations show that just a small fraction of labile bonds leads to a roughly 25% increase in the stress needed to induce fracture. Thus, the labile bonds can significantly improve the tensile strength of the material. The findings provide guidelines for creating high-strength, self-healing materials.