Multi‐Stimuli Responsive Nanoaggregates Based on Bis‐Urea Motifs Bearing Terminal Tertiary Amines

Supramolecular assembles constructed through non‐covalent interactions hold immense potential for smart material applications due to their dynamic responsiveness. Herein, 1,1'‐(hexane‐1,6‐diyl)bis(3‐(3‐(dimethylamino)propyl)urea) (DMAPBU) is synthesized via an addition reaction, self‐assembled in water through bis‐urea quadruple hydrogen bonding, forming a dynamic network. Systematic investigations reveal this kind of supramolecular nanoaggregates can respond to thermal, CO₂, CO₂ analogs, halide anions, even synergistic effectors. The thermal‐sensitive experiments show that DMAPBU exhibits a concentration‐dependent upper critical solution temperature (UCST) behavior, modulated by hydrogen bonds partial reorganization. CO₂ exposure triggers almost irreversible ammonium carbamate formation and terminal tertiary amines protonation, eliminating UCST transitions. KHCO₃ addition causes a similar concentration‐dependent change in this system. While K₂CO₃ modulates the UCST over a certain temperature range. Halide anions elevate UCST thresholds through size‐dependent bifurcated hydrogen bonding. The temperature‐dependent 1 H‐NMR measurements elucidate the mechanism of thermo‐tunable behavior of DMAPBU. AFM analyses confirm CO₂‐triggered morphological transitions from elongated fibers to shortened rods, aligning with disrupted hydrogen bonding and enhanced hydrophilicity. Remarkably, synergistic effectors (K₂CO₃/KHCO₃/KOH/CO 2 ) enable programmable UCST and LCST transitions, broadening tunability. This work demonstrates smart molecular design integrating structural adaptability with multi‐stimuli responsiveness, offering insights for dynamic materials in sensing and adaptive systems.