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Abstract Herein, we examine pathway complexity in the supramolecular polymerization of a novelm‐terphenyl bis‐urea macrocycle. Designed to induce kinetically metastable states, the macrocycle‘s concentration‐dependent aggregation was studied via1H NMR and IR spectroscopy in THF and CHCl₃. Temperature‐dependent UV‐Vis spectroscopy in water/THF revealed a cooperative nucleation‐growth mechanism, indicated by a shift in λmax to longer wavelengths upon cooling. Morphological studies using DLS, AFM, and SEM demonstrated fibrous aggregate formation. Thermal hysteresis observed in assembly‐disassembly cycles indicated kinetically trapped species, with cooling governed by kinetic control and heating by thermodynamic processes. Deviations in ΔH values during cooling, compared to van′t Hoff analysis and alignment of heating ΔH values with thermodynamic predictions, reinforced this distinction. Spontaneous nucleation retardation, resulting from monomer trapping, led to lag times of up to 50 minutes under specific conditions. Computational studies revealed the parallel urea conformation as the more stable monomer configuration, whereas the antiparallel conformation is more stable in dimers. By probing pathway complexity of the macrocycle, we demonstrate a distinct ability to control and stabilize kinetically trapped states, broadening the scope for designing macrocyclic supramolecular polymers with tailored properties. This work deepens our understanding of supramolecular dynamics, exploring ON‐pathway mechanisms and advancing tunable supramolecular materials.
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This content will become publicly available on May 9, 2026
Redox‐Enabled Pathway Complexity in Supramolecular Hydrogels
Abstract Pathway complexity in supramolecular assemblies presents a unique opportunity for a single, relatively simple system to exhibit a wide range of properties allowing for multifunctionality. In this study, we report redox‐enabled pathway complexity in amino acid‐functionalized perylene diimides (PDIs) and its consequence for the macroscopic hydrogel network. We show that chemical reduction and subsequent oxidation enable a kinetically trapped state which transforms into different network morphologies in response to heat and time. Our finding that pathway complexity in supramolecular systems can alter bulk material properties suggests the potential for future development of dynamic materials that achieve multiple macroscopic functions with a single building block.
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- Award ID(s):
- 2011967
- PAR ID:
- 10590403
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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