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Abstract Supramolecular polymer networks contain non-covalent cross-links that enable access to broadly tunable mechanical properties and stimuli-responsive behaviors; the incorporation of multiple unique non-covalent cross-links within such materials further expands their mechanical responses and functionality. To date, however, the design of such materials has been accomplished through discrete combinations of distinct interaction types in series, limiting materials design logic. Here we introduce the concept of leveraging “nested” supramolecular crosslinks, wherein two distinct types of non-covalent interactions exist in parallel, to control bulk material functions. To demonstrate this concept, we use polymer-linked Pd2L4metal–organic cage (polyMOC) gels that form hollow metal–organic cage junctions through metal–ligand coordination and can exhibit well-defined host-guest binding within their cavity. In these “nested” supramolecular network junctions, the thermodynamics of host-guest interactions within the junctions affect the metal–ligand interactions that form those junctions, ultimately translating to substantial guest-dependent changes in bulk material properties that could not be achieved in traditional supramolecular networks with multiple interactions in series.
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Viscoelastic Supramolecular Networks Based on Guanidinium‐Oxyanion Interactions
We describe the synthesis and characterization of supramolecular networks based on charge‐assisted hydrogen bonding interactions of guanidinium and oxyanion functionalities. Although they are constructed entirely of small‐molecule components, these materials display properties such as a glass transition and time‐ and temperature‐dependent viscoelastic rheological behavior. These properties can be tuned by the choice of each network component:Tgvaries by over 50°C in the studied networks, and relaxation times scaled with changes toTg. However, these supramolecular materials are inherently degradable and thermally reversible as no covalent macromolecular structure is formed
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- Award ID(s):
- 2105149
- PAR ID:
- 10594299
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Journal of Polymer Science
- ISSN:
- 2642-4150
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/pol.20250048
