All-polymer dynamical ionogel-like materials with benzyl-mediated ultra-strong adhesion for flexible sensor application

Abstract

Ionogels, as the cutting-edge soft materials, have aroused tremendous interests in flexible electronics. However, the present ionogels are often achieved through incorporating ionic liquids (ILs) into the polymer networks, which are still suffering from the fragilities of ILs leakage and weak mechanical performances. Herein, dynamic double-network ionogel-like materials (IGMs) were fabricated in the absence of small molecule ILs. The novel IGMs could be facilely prepared via the copolymerization of functional IL monomers acting as the first network, followed by anion exchange and ring-opening polymerization of lipoic acid (LA). Especially, when benzyl-modified IL was added as the third monomer, the newly-developed poly(ionic liquid) (PIL) IGMs integrated various excellent performances, including unprecedented adhesion strength, stretchability, self-healing and absorption capabilities. Flexible sensors fabricated by the novel PIL-based IGMs could distinguish the facial expressions and body motions accurately. Moreover, PIL-based IGMs could be easily recycled and reprocessed. Thus, our finding puts forward a readily accessible feedstock for the fabrication of multifunctional all-polymer IGMs.