Eco‐Friendly, Recyclable Supramolecular Inks Incorporating Multi‐Walled Carbon Nanotubes

In contemporary society, with its emphasis on environmental stewardship, the development of “green” (eco‐friendly) inks is of paramount importance. These inks are utilized across a broad spectrum of applications, ranging from the printing of packaging material to the 3D printing of functional components. This study explores the synthesis of eco‐friendly, biodegradable supramolecular polymer materials predicated on ureido‐pyrimidinone (UPy). The subsequent formulation of these materials into functional inks is achieved by the incorporation of multi‐walled carbon nanotubes (MWCNTs). These resultant inks exhibit outstanding photothermal conversion properties, robust electrical conductivity, intrinsic self‐repair capabilities, and superior writability. Moreover, this research demonstrates the recyclability of MWCNTs within the ink matrix, exhibiting a recovery efficiency of ≈90%. Such a high recovery rate offers a novel perspective on the sustainable reuse of conductive fillers in polymer‐based inks. Photothermal behavior is observed for supramolecular inks with different multi‐walled carbon nanotube (MWCNT) contents over a 10‐min period. Both the duration of irradiation and the concentration of MWCNTs are proportional to the increase in temperature.