Surface-segregated nanodomains for a fast room-temperature self-healing elastomer with exceptional scratch and chemical resistance and folding reliability

Abstract

Achieving rapid autonomous repair in a mechanically robust polymer coating remains a long-standing challenge for flexible displays and electronics. Here, we report a room-temperature self-healing elastomer that resolves this trade-off by incorporating specially designed fluorinated imide additives into a crosslinked network. The fluorinated segments migrate spontaneously to the surface and form nanometer-scale domains that function as an in situ rigid reinforcement layer. Meanwhile, the imide groups form multiple reversible bonds in the bulk, yielding a densely crosslinked yet dynamic network. This hierarchical architecture effectively decouples surface hardness from matrix flexibility by integrating a hard, chemically resistant surface layer with a flexible, self-healing interior. The resulting elastomer combines properties rarely achieved in a single material. It autonomously heals surface scratches within 10 s at room temperature, exhibits a pencil hardness of 4H that surpasses commercially available optical-grade plastics, resists immersion in toluene for over 18 h while retaining more than 90 % optical transparency, and withstands over 200,000 folding/unfolding cycles at a 1.5 mm radius without cracks or delamination. By combining mechanical durability and flexibility with rapid self-healing, this work addresses a key limitation of conventional self-healing polymers. This material design offers a general strategy with broad implications for enhancing the reliability and service life of flexible displays, wearable sensors, and other next-generation electronic devices.