Supramolecular\nAssociation of a Block Copolymer via\nStrong Hydrogen Bonding to Form Self-Healable Ionogels

The drive to enhance the operational\ndurability and reliability\nof stretchable and wearable electronic and electrochemical devices\nhas led to the exploration of self-healing materials that can recover\nfrom both physical and functional failures. In the present study,\nwe fabricated a self-healable solid polymer electrolyte, referred\nto as an ionogel, using reversible hydrogen bonding between the ureidopyrimidone\nunits of a block copolymer (BCP) network swollen in an ionic liquid\n(IL). The BCP consisted of poly(styrene-<i>b</i>-(methyl\nacrylate-<i>r</i>-ureidopyrimidone methacrylate)) [poly(S-<i>b</i>-(MA-<i>r</i>-UPyMA)], with the IL-phobic polystyrene\nforming micellar cores that were interconnected via intercorona hydrogen\nbonding between the ureidopyrimidone units. By precisely regulating\nthe molecular weight and the composition of the hydrogen-bondable\nmotifs, the mechanical, electrical, and self-healing characteristics\nof the ionogel were systematically evaluated. The resulting ionogel\nsamples exhibited suitable stretchability, ionic conductivity, and\nroom-temperature self-healability due to reversible hydrogen bonding.\nTo highlight the applicability of the self-healing ionogel as a high-capacitance\ngate insulator, an electrolyte-gated transistor (EGT) was fabricated\nusing a poly(3-hexylthiophene-2,5-diyl) semiconductor, and the performance\nof the EGT was fully recovered from a complete cut without any external\nstimuli.