Researchers at the University of Osaka have synergistically combined three strategies for energy dissipation to enhance the toughness of elastomers. Rotaxane molecules with sacrificial bonds are incorporated into an elastomer. Under increasing external force, three mechanisms become sequentially activated: sliding of the rotaxane molecules, force-induced bond scission in the rings to form linear chains, and entanglement of the resulting chains. A polyurethane elastomer synthesized using this strategy was five times tougher than a conventional polyurethane.