Affiliation:
1. Department of Chemistry Indian Institute of Technology Hyderabad, Kandi Sangareddy Telangana 502284 India
2. Centre for Computational and Data Science Indian Institute of Technology Kharagpur West Bengal 721302 India
3. Toyota Research Institute of North America Ann Arbor Michigan 48105 USA
Abstract
AbstractUnderstanding solvent‐solute interactions is essential to designing and synthesising soft materials with tailor‐made functions. Although the interaction of the solute with the solvent mixture is more complex than the single solvent medium, solvent mixtures are exciting to unfold several unforeseen phenomena in supramolecular chemistry. Here, we report two unforeseen pathways observed during the hierarchical assembly of cationic perylene diimides (cPDIs) in water and amphiphilic organic solvent (AOS) mixtures. When the aqueous supramolecular polymers (SPs) of cPDIs are injected into AOS, initially kinetically trapped short SPs are formed, which gradually transform into thermodynamically stable high aspect ratio SP networks. Using various experimental and theoretical investigations, we found that this temporal evolution follows two distinct pathways depending on the nature of the water‐AOS interactions. If the AOS is isopropanol (IPA), water is released from cPDIs into bulk IPA due to strong hydrogen bonding interactions, which further decreases the monomer concentration of cPDIs (Pathway‐1). In the case of dioxane AOS, cPDI monomer concentration further increases as water is retained among cPDIs (Pathway‐2) due to relatively weak interactions between dioxane and water. Interestingly, these two pathways are accelerated by external stimuli such as heat and mechanical agitation.
Funder
Science and Engineering Research Board