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Vitrimers, an emerging class of polymer materials, are thermosets with dynamic covalent cross-linkers, allowing for topology rearrangement at elevated temperatures. However, vitrimers have several drawbacks, such as slow response times and often lack photothermal catalytic activity. Herein, we demonstrate that embedding functional nanofillers, i.e., hierarchically assembled plasmonic gold nanoparticles (AuNPs) on graphene nanoplatelets (GNPIs) into a vitrimer matrix, induces an ultrafast photothermal healing response. Unlike previous research that mainly focused on bulk materials, our exploration of vitrimer nanocomposite films uncovers unique advantages, such as optical transparency in the visible wavelength, flexibility, and ultrafast localized healing upon exposure to a 532 nm wavelength laser. These remarkable properties of vitrimer nanocomposite films were demonstrated with three various filler compositions and concentrations, where AuNPs/GNPls serve as a powerful filler. Photothermally activated self-healing of these hybrid materials is demonstrated by taking advantage of the localized surface plasmon resonance (LSPR) of AuNPs and the broad absorbance wavelength and high thermal conductivity of GNPls. Furthermore, profilometry is utilized to quantify the volume percent recovery of healing, providing quantitative evidence of increased healing with a higher filler concentration and laser dosage. This localized, ultrafast healing is pivotal for future coating applications, where bulk heating could lead to undesirable deformations. Our comprehensive understanding of the role of filler composition, filler concentration, and laser dosage in the self-healing properties of films opens up a wide array of potential applications for these light-responsive functional materials. The potential applications of these materials span from self-healing coatings to flexible electronics, inspiring a new era of innovative solutions. [ABSTRACT FROM AUTHOR]

Corrugations can dramatically change the effective mechanical properties of a thin sheet. Such alternating ridges and grooves are typically fabricated by mechanical processing. Herein, the ability to trigger and tune corrugations within thin (≈300 µm thick) thermoplastic sheets rapidly (≈seconds) using only light is reported. Patterns of black ink on the otherwise transparent, flimsy sheet preferentially adsorb external IR light, inducing localized heating of the underlying polymer. This heating causes localized shrinkage of the polymer, producing folds in the sheets; collectively, these folds result in corrugations of controlled geometry. Depending on orientation, these corrugations dramatically increase stiffness or extensibility, similar to corrugated roofs (stiff) or accordions (extensible). In the direction parallel to the folds, the maximum load‐carrying capacity increases by two orders of magnitude relative to the non‐corrugated sheet; perpendicular to the folds, the effective modulus decreases by four orders of magnitude. In addition to tuning effective mechanical properties, the ability to corrugate flat surfaces using light has implications for assembling 3D objects from substrates printed in 2D (such as lithographically patterned electronics) or 3D structures shipped in a flat state. Herein, the process of forming such structures is discussed and their properties are characterized. [ABSTRACT FROM AUTHOR]