RESUMEN
Chemical fuel-driven supramolecular systems have been developed showing out-of-equilibrium functions such as transient gelation and oscillations. However, these systems suffer from undesired waste accumulation and they function only in open systems. Herein, we report non-equilibrium supramolecular polymerizations in a closed system, which is built by viologens and pyranine in the presence of hydrazine hydrate. On shaking, the viologens are quickly oxidated by air followed by self-assembly of pyranine into micrometer-sized nanotubes. The self-assembled nanotubes disassemble spontaneously over time by the reduced agent, with nitrogen as the only waste product. Our mechanosensitive dissipative system can be extended to fabricate a chiral transient supramolecular helix by introducing chiral-charged small molecules. Moreover, we show that shaking induces transient fluorescence enhancement or quenching depending on substitution of viologens. Ultrasound is introduced as a specific shaking way to generate template-free reproducible patterns. Additionally, the shake-driven transient polymerization of amphiphilic naphthalenetetracarboxylic diimide serves as further evidence of the versatility of our mechanosensitive non-equilibrium system.
RESUMEN
In most synthetic nanoreactor systems, catalysed products do not promptly diffuse away from the nanoreactor, which leads to lower than expected catalytic efficiencies. To address the diffusion problem, transient polymer micelle nanoreactor systems were achieved using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) as the fuel and activated esters as the energy dissipating units. These demonstrated pathway-dependent catalytic properties for transient micelles: product inhibition was observed or efficiently eliminated depending on EDC reloading in the metastable stage or after full dissipation for transient micelles.
