Tricomponent Supramolecular Multiblock Copolymers with Tunable Composition via Sequential Seeded Growth

Caught in Action: Visualizing Dynamic Nanostructures Within Supramolecular Systems Chemistry

Supramolecular systems chemistry has been an area of active research to develop nanomaterials with life-like functions. Progress in systems chemistry relies on our ability to probe the nanostructure formation in solution. Often visualizing the dynamics of nanostructures which transform over time is a formidable challenge. This necessitates a paradigm shift from dry sample imaging towards solution-based techniques. We review the application of state-of-the-art techniques for real-time, in situ visualization of dynamic self-assembly processes. We present how solution-based techniques namely optical super-resolution microscopy, solution-state atomic force microscopy, liquid-phase transmission electron microscopy, molecular dynamics simulations and other emerging techniques are revolutionizing our understanding of active and adaptive nanomaterials with life-like functions. This Review provides the visualization toolbox and futuristic vision to tap the potential of dynamic nanomaterials.

Expanding the Scope of Metastable Species in Hydrogen Bonding‐Directed Supramolecular Polymerization

We reveal unique hydrogen (H‐) bonding patterns and exploit them to control the kinetics, pathways and length of supramolecular polymers (SPs). New bisamide‐containing monomers were designed to elucidate the role of competing intra‐ vs. intermolecular H‐bonding interactions on the kinetics of supramolecular polymerization (SP). Remarkably, two polymerization‐inactive metastable states were discovered. Contrary to previous examples, the commonly assumed intramolecularly H‐bonded monomer does not evolve into intermolecularly H‐bonded SPs via ring opening, but rather forms a metastable dimer. In this dimer, all H‐bonding sites are saturated, either intra‐ or intermolecularly, hampering elongation. The dimers exhibit an advantageous preorganization, which upon opening of the intramolecular portion of the H‐bonding motif facilitates SP in a consecutive process. The retardation of spontaneous self‐assembly as a result of two metastable states enables length control in SP by seed‐mediated growth.