Dilution-induced gel-sol-gel-sol transitions by competitive supramolecular pathways in water
Lu Su, Jesús Mosquera, Mathijs F. J. Mabesoone, Sandra M. C. Schoenmakers, Cyprien Muller, Marle E. J. Vleugels, Shikha Dhiman, Stefan Wijker, Anja R. A. Palmans, E. W. Meijer
Abstract
Fascinating properties are displayed by synthetic multicomponent supramolecular systems that comprise a manifold of competitive interactions, thereby mimicking natural processes. We present the integration of two reentrant phase transitions based on an unexpected dilution-induced assembly process using supramolecular polymers and surfactants. The co-assembly of the water-soluble benzene-1,3,5-tricarboxamide (BTA-EG 4 ) and a surfactant at a specific ratio yielded small-sized aggregates. These interactions were modeled using the competition between self-sorting and co-assembly of both components. The small-sized aggregates were transformed into supramolecular polymer networks by a twofold dilution in water without changing their ratio. Kinetic experiments show the in situ growth of micrometer-long fibers in the dilution process. We were able to create systems that undergo fully reversible hydrogel-solution-hydrogel-solution transitions upon dilution by introducing another orthogonal interaction.