Aggregate Engineering in Supramolecular Polymers via Extensive Non-covalent Networks

Abstract

Aggregate engineering of non-covalent networks enables thermo-mechanical versatility of supramolecular polymers, particularly the stimuli-responsive phase transitions and intrinsically damage-healing abilities. However, most non-covalent networks are vulnerable at elevated temperatures, which significantly suppress the robustness of supramolecular polymers. Herein, ureidocytosine (UCy) motifs that can form extensive non-covalent networks and thus robust molecular aggregates via multivalent hydrogen bonds and aromatic stackings, are proposed to enable precise programming of the thermo-mechanical versatility. Molecular simulations reveal that the enthalpic contributions from the UCy aggregates play dominant roles to compensate the entropic loss from the redistributions of polymeric spacers and stabilize the non-covalent networks over wide temperature windows. Such aggregate-level strategy offers prospects for applications which require thermo-mechanical versatility of supramolecular polymers, such as 3D printing, microfabrication and damage-healing coating.