Aggregate Engineering in Supramolecular Polymers via Extensive Non-covalent Networks

Aggregate engineering of non-covalent networks endows supramolecular polymers with thermo-mechanical versatility, stimuli-responsive phase transitions and intrinsic damage-healing capabilities. However, most non-covalent networks are vulnerable at elevated temperatures, which suppresses the robustness of supramolecular polymers. Herein, ureidocytosine (UCy) motifs, which are capable of forming 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.