In this study, high-crystallinity single walled carbon nanotubes (H-SWNTs) were prepared by high-temperature thermal annealing at 1800 °C and a self-heating shape memory polyurethane nanocomposite with excellent self-heating characteristics was developed within a few seconds by irradiation with near-infrared rays. With a simple method (heat treatment), impurities at the surface of H-SWNTs were removed and at the same time the amorphous structure converted into a crystalline structure, improving crystallinity. Therefore, high conductivity (electric, thermal) and interfacial affinity with PU were increased, resulting in improved mechanical, thermal and electric properties. The electrical conductivity of neat polyurethane was enhanced from ~10–11 S/cm to 4.72 × 10−8 S/cm, 1.07 × 10−6 and 4.66 × 10−6 S/cm, while the thermal conductivity was enhanced up to 60% from 0.21 W/mK, 0.265 W/mK and 0.338 W/mK for the composites of 1, 3 and 5 wt%, respectively. Further, to achieve an effective photothermal effect, H-SWNTs were selected as nanofillers to reduce energy loss while increasing light-absorption efficiency. Thereafter, near-infrared rays of 818 nm were directly irradiated onto the nanocomposite film to induce photothermal properties arising from the local surface plasmon resonance effect on the CNT surface. A self-heating shape memory composite material that rapidly heated to 270 °C within 1 min was developed, even when only 3 wt.% of H-SWNTs were added. The results of this study can be used to guide the development of heat-generating coating materials and de-icing materials for the wing and body structures of automobiles or airplanes, depending on the molding method.

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Fluorescent polymers have exciting applications in sensing, imaging, and probes. Agricultural waste is increasingly being used to develop fluorescent nanomaterials due to technology, cost, and waste management advantages. This study developed fluorescent carbon‐based nanomaterials, that is, potassium doped graphene oxide (K‐GO) from Quercus ilex waste and used them to optimize fluorescent epoxy nanocomposites. The resulting nanocomposites showed significant enhancement in tensile strength with only 0.05 wt% of the renewable nanomaterial. The developed fluorescent epoxy nanocomposites have enhanced thermal and mechanical properties and can be used in sensing, imaging, and other applications.Highlights A greener and easier approach to synthesizing K‐GO from Quercus ilex seeds. Development of fluorescent epoxy composites with K‐GO. Tensile strength is enhanced by adding only 0.05 wt% K‐GO. Thermal stability was improved by adding K‐GO. Developed composites can be applied to sensing and UV‐shielding in the future.

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