Self-Healing Performance in Polymers After Tensile Fracture: Mechanisms and Influences

Conventional polymers face a fundamental challenge in achieving autonomous healing after tensile fracture, as such fractures generate stretched chains, rough surfaces, and misaligned bonding moieties that hinder efficient rebonding. To overcome this, we designed a proof-of-concept polymer that integrates a stable dynamic network with a high chain mobility. This unique combination enables rapid, time-insensitive self-healing. Using the traditional cut-healing method as a benchmark, the material recovers 92% of its original mechanical properties within 10 min at room temperature, maintaining this high efficiency even after 216 h of separation. For more realistic tensile fractures, a fractured sample regains over 60% of its original tensile strength after 96 h at 25 °C and more than 90% after 72 h at 60 °C. To accelerate the fracture-healing process, we developed a surface remodeling protocol that achieves over 90% efficiency in just 10 min at room temperature, matching the performance of ideal cut healing, albeit with some irreversible dimensional change. Finally, a self-welding protocol is proposed to eliminate this dimensional loss. This work provides a strategic design and processing framework for healing realistic mechanical damage in polymers.